What are superalloys

What are superalloys?

Superalloy is a kind of metal material based on iron, nickel and cobalt, which can work at high temperature above 600 ℃ and under certain stress for a long time. It has excellent high temperature strength, good oxidation resistance and hot corrosion resistance, good fatigue performance, fracture toughness and other comprehensive properties. It is also known as “superalloy”. It is mainly used in aerospace and energy fields. Commonly used are GH3030, GH4169, GH4141, GH5188, GH3128, GH4145 and so on.

Types of Superalloys

The traditional classification of superalloy materials can be carried out according to the following three ways: according to the types of matrix elements, the types of alloy reinforcement and the material forming methods.

By type of matrix element

(1) iron base superalloy
Iron base superalloy can be called heat-resistant alloy steel. The base of the steel is Fe, and a small amount of Ni, Cr and other alloy elements are added. The heat-resistant alloy steel can be divided into martensite, austenite, pearlite and ferritic heat-resistant steel according to its normalizing requirements.
(2) nickel base superalloy
Nickel content of Ni base superalloy is more than half, which is suitable for working conditions above 1000 ℃, and the creep resistance and compressive yield strength can be greatly improved by solid solution and aging process. The range of Ni based superalloys is far beyond the use of Fe based and Co based superalloys. At the same time, nickel base superalloy is also one of the most productive and most used superalloys in China. Many turbine blades and combustion chambers of turboengines, even the turbocharger, also use nickel based alloy as the preparation material. For more than half a century, the high temperature material used in Aeroengine has been able to withstand high temperature from 750 ℃ in the late 1940s to 1200 ℃ in the late 1990s. It should be said that this great improvement also promotes the rapid development of casting process and surface coating.
(3) cobalt based superalloy
Cobalt based superalloy is based on cobalt, which accounts for about 60% of the total. Meanwhile, Cr, Ni and other elements are needed to improve the heat resistance of superalloy. Although the high temperature alloy has better heat resistance, it is difficult to process because of the low cobalt resource output in various countries, and the amount is not much. It is usually used in high temperature conditions (600-1000 ℃) and high temperature parts subjected to extreme complex stress for a long time, such as the working blades, turbine disk, hot end parts of combustion chamber and aerospace engine of aeroengine. In order to obtain better heat resistance, elements such as W, Mo, Ti, Al, CO should be added in the preparation to ensure its superior thermal and fatigue resistance.

Alloy strengthening type

According to the type of alloy strengthening, superalloys can be divided into solid solution reinforced superalloys and aging precipitation strengthening alloys.
(1) solid solution strengthening type
The so-called solid solution strengthening type is to add some alloy elements to the high temperature alloy of iron, nickel or cobalt base to form single-phase austenite structure. The solute atoms cause the matrix lattice distortion of solid solution, and increase the sliding resistance in the solid solution and strengthen it. Some solute atoms can reduce the layer error energy of alloy system, improve the tendency of dislocation decomposition, which makes cross slip difficult to carry out, and the alloy is strengthened to achieve the purpose of strengthening superalloy.
(2) aging precipitation strengthening
Aging precipitation strengthening is a heat treatment process for alloy workpiece after solid solution treatment and cold plastic deformation, which is placed at higher temperature or kept its properties at room temperature. For example, GH4169 alloy has a maximum yield strength of 1000 MPa at 650 ℃ and the alloy temperature of blade can reach 950 ℃.

Material forming method

The material forming methods are divided into: Casting superalloys (including ordinary casting alloy, single crystal alloy, directional alloy, etc.), deformed superalloy, powder metallurgy superalloy (including ordinary PM and oxide dispersion strengthened superalloy).
(1) casting superalloy
The alloy material of parts and components directly made by casting method is called casting superalloy. According to the composition of the alloy matrix, it can be divided into three types: iron base casting superalloy, nickel based superalloy and drill base casting superalloy. According to the crystallization mode, it can be divided into four types: polycrystalline casting superalloy, directional solidification casting superalloy, directional eutectic casting superalloy and single crystal casting superalloy.
(2) deformed Superalloy
It is still the most used material in aeroengine, and it is widely used at home and abroad. The annual output of deformed superalloy in China is about 1 / 8 of that of the United States. Taking GH4169 alloy as an example, it is the most widely used variety at home and abroad. In China, bolts, compressors, wheels and oil dump plates of turboshaft engines are the main parts. With the maturity of other alloy products, the usage of deformed superalloy may gradually decrease, but it will still be the dominant position in the next decades.
(3) new Superalloy
It includes many sub product fields, such as powder superalloy, titanium aluminum intermetallic compound, oxide dispersion strengthening superalloy, corrosion resistant superalloy, powder metallurgy and nano materials

  • ① The third generation of Powder Superalloy has been improved in alloying degree, which makes it take into account the advantages of the previous two generations, and has obtained higher strength and lower damage. The production process of Powder Superalloy is becoming more mature. In the future, it may be carried out from the following aspects: powder preparation, heat treatment process, computer simulation technology, dual energy powder disk;
  • ② The intermetallic compounds of titanium aluminum series have been developed to the fourth generation, and gradually expand towards the two directions of multi trace and large amount of micro elements. Hamburg University, Kyoto University of Japan and GKSS center in Germany have been extensively studied. The intermetallic compounds of titanium aluminum series have been widely used in the fields of ships, biomedical and sports supplies;
  • ③ Oxide dispersion reinforced superalloys are part of powder superalloys. There are more than 20 kinds of alloys being produced and developed, which have high temperature strength and low stress coefficient. They are widely used in heat-resistant and anti-oxidation parts of gas turbine, advanced aeroengines, petrochemical reaction reactors, etc;
  • ④ Corrosion resistant superalloy is mainly used to replace refractory and heat-resistant steel, and is used in the field of architecture and aerospace.

GH3128

GH3128 is a Ni Cr based solid solution strengthened wrouGHt superalloy, and its service temperature is below 950 ℃. 16% w (W + Mo) was added to the alloy for solution strengthening, and boron, cerium and zirconium were added to purify and strengthen the grain boundaries. The alloy has high plasticity, high creep and rupture strength, good oxidation resistance, stamping and welding process properties, and its comprehensive properties are better than those of similar nickel base solid solution strengthening alloys such as GH3044 and GH3536. It is suitable for making the flame tube and afterburner shell of aero-engine combustor working at 950 ℃ for a long time. The main products are cold rolled sheet, hot rolled plate, bar, forging, wire and pipe.
GH3128 alloy has been used in the manufacture of aero-engine flame tube, diffuser, afterburner, tail nozzle, adjusting plate, stabilizer, diffuser and gas pipe, etc. the batch production and use of GH3128 alloy are good. The alloy is also widely used in temperature thermocouple protection tube, fluxgate, magnetometer probe, skeleton material, W and Mo reduction sintering boat, rail locomotive precombustion chamber nozzle and other structural parts under high temperature oxidation atmosphere. W-2 enamel layer can be used for effective protection when parts work at high temperature. After long-term aging, the alloy has some defects μ Phase precipitation.

Chemical constituents of GH3128

Element C Cr Ni W Mo Al Ti Fe
Mass fraction /% ≤0.05 19.0-22.0 Balance 7.5-9.0 7.5-9.0 0.4-0.8 0.4-0.8 ≤2.0
Element Zr B Ce Si P S Mn
Mass fraction /% ≤0.06 ≤0.005 ≤0.05 ≤0.8 ≤0.013 ≤0.013 ≤0.5

Physical and mechanical properties of GH3128

Density

Melting point

8.81g/cm3

1340~1390℃

Varieties

Sample state

θ/℃

Tensile property

Persistent performance

σb/MPa

δ5/%

σ/MPa

δ/mm

t/h

δ5/%

Not less than

Hot rolled plate

Delivery status

20

735

40

Delivery status + 1200 ℃, air cooling

950

175

40

Cold rolled sheet

Delivery status

20

735

40

Delivery status + 1200 ℃, air cooling

950

175

40

Standard

54

>1.2

≤1.2

≥23

≥20

Actual measurement

Actual measurement

Standard 

39

≥1.5

<1.5~1.0< span=””>

≤1.0

≥100

≥80

≥70

Actual measurement

Actual measurement

Actual measurement

Heat treatment system of GH3128

  • A) For cold rolled and hot rolled plates, (1140 ~ 1180) ℃ / AC, the holding time depends on the thickness of the plate;
  • B) Medium and heavy plate( δ 15mm ~ 65mm), (1180 ~ 1200) ℃ / AC, the holding time depends on the thickness of the plate;
  • C) Hot rolled and forged bars, (1140 ~ 1200) ℃ / AC ×( 1.5~2 ) h/AC;
  • D) For the cake material, (1180 ~ 1200) ℃ / AC, the selection of holding time should ensure that the parts can be heat permeable, solid solution fully or meet the annealing requirements.

GH3128 (GH128) is a nickel base alloy strengthened by solid solution of tungsten and molybdenum and grain boundaries strengthened by boron, cerium and zirconium. It has high plasticity, high creep strength, good oxidation resistance, stamping and welding properties. Its comprehensive properties are better than those of similar nickel base solid solution alloys such as GH3044 and GH3536. It is suitable for manufacturing combustor flame tube, afterburner shell, adjusting plate and other high-temperature parts of aero-engine working at 950 ℃ for a long time. The main products are cold-rolled sheet, as well as hot-rolled plate, bar, forging, wire and pipe. The solid solution temperature of delivery state is 1140 ~ 1180 ℃, air cooling. The high temperature performance was tested after supplementary solution treatment at 1200 ℃. Cold rolled sheet 0.8 ~ 4.0 mm, hot rolled sheet 4 ~ 14 mm, cold drawn welding wire Φ 0.3~10mm. Cold rolled plate and hot rolled plate are suitable for solution and pickling; The welding wire should be in the state of cold drawing, semi hard or solid solution and pickling. Non vacuum or vacuum induction furnace with electroslag remelting. The alloy is suitable for manufacturing components of aero-engine combustion chamber and afterburner working below 950 ℃ with good effect.

Material technical standard:

  • GJB 1952-1994 specification for cold rolled aeronautical superalloy sheets
  • GJB 2612-1996 specification for cold drawn superalloy wire for welding
  • GJB 2612-1996 specification for aeronautical hot rolled superalloy plates

The microstructure of GH3128

The microstructure of the alloy is single-phase austenite in solid solution state, with a small amount of fine and uniform distribution of tin and M6C.

Process performance and requirements

  • 1. The furnace temperature of ingot forging is not higher than 700 ℃, and the final forging temperature is higher than 900 ℃.
  • 2. The average grain size of the alloy is closely related to the deformation degree and final forging temperature.
  • 3. The alloy can be welded by argon arc welding, spot welding and seam welding.

Performance requirements of GH3128

Thermal performance of GH3128

The melting temperature range of GH3128 (GH128) is 1340 ~ 1390 ℃.
The thermal conductivity of GH3128 (GH128) is shown in table 2-1 and table 2-1.

θ/℃

100

200

300

400

500

600

700

800

900

950

λ/(W/(m·C))

11.30

12.56

14.24

15.49

16.75

18.42

19.68

21.35

23.02

23.86

The coefficient of linear expansion of GH3128 (GH128) is shown in table 2-2:

θ/℃

18~100

18~200

18~300

18~400

18~500

18~600

18~700

18~800

18~900

18~1000

α/10-6C-1

11.25

11.86

12.68

12.80

13.37

13.68

14.46

15.19

15.66

15.29

The thermal diffusivity of GH3128 (GH128) is shown in table 2-3:

θ/℃

25

100

200

300

400

500

600

700

800

Q/(10-6m2/S))

2.30

2.49

2.78

3.08

3.39

3.69

3.88

3.92

4.16

Density of GH3128 (GH128)

  • ρ= 8.81g/cm3

The electrical resistivity of GH3128 (GH128) is shown in table 2-4:

θ/℃

17

850

900

950

1000

1050

1100

1150

p/(10-6Ω.M))

1.37

1.42

1.39

1.40

1.39

1.38

1.38

1.39

Chemical properties of GH3128

The oxidation rate of GH3128 (GH128) after 100 h in air is shown in table 2-5:

θ/℃

900

1000

1100

Oxidation rate/(g/(M3·h))

0.055

0.236

0.269

Application fields of GH3128

  • Combustion chamber flame tube, afterburner shell and regulating plate of Aeroengine;
  • Structure of gas turbine combustor;
  • Turbine engine combustion chamber components;
  • Afterburner components.

GH4169

Another characteristic of the alloy is that the alloy structure is particularly sensitive to the hot working process. By mastering the law of precipitation and dissolution in the alloy and the relationship between the structure, process and properties, reasonable and feasible process procedures can be formulated for different requirements, and various parts that can meet different strength levels and requirements can be obtained. The products are forgings, forged bars, rolled bars, cold-rolled bars, round cakes, rings, plates, strips, wires, tubes, etc. It can be made into disc, ring, blade, shaft, fastener, elastic element, plate structure, gearbox and other parts, which can be used in aviation for a long time.

Material grade of GH4169

  • GH4169(GH169) 

Similar brands of GH4169

  • Inconel718 (USA), nc19fenb (France)

Technical standards for GH4169 materials

  • GJB 2612-1996 specification for cold drawn superalloy wire for welding
  • HB 6702-1993 “GH4169 alloy bars for wz8 series”
  • Q / 6S 1034-1992 GH4169 alloy bars for high temperature fasteners
  • GH4169 alloy forgings (Q / 3b 548-1996)
  • GH4169 alloy forgings (Q / 3b 548-1996)
  • Q / 3b 4048-1993 yzGH4169 alloy bars
  • Q / 3b 4050-1993 GH4169 alloy sheet
  • GH4169 alloy wire (Q / 3b 4051-1993)
  • GB / t14992-2005 Superalloy

Chemical constituents of GH4169

The chemical composition of the alloy can be divided into three categories: standard composition, high-quality composition and high-purity composition, as shown in Table 1-1. The high-quality components can reduce carbon and increase niobium on the basis of standard components, so as to reduce the amount of niobium carbide, reduce the amount of fatigue source and strengthening phase, improve the content of anti fatigue, and improve the purity and comprehensive properties of materials.
The content of boron in GH4169 alloy for nuclear power application should be controlled (other elements remain unchanged), and the specific content should be determined by both parties throuGH negotiation. When ω( B) When it is less than or equal to 0.002%, the alloy grade is GH4169A to distinguish it from GH4169 alloy used in aerospace industry.

Type

C

Cr

Ni

Co

Mo

Al

Ti

Fe

Standard

≤0.08

17.0~21.0

50.0~55.0

≤1.0

2.80~3.30

0.30~0.70

0.75~1.15

Balance

High quality

0.02~0.06

17.0~21.0

50.0~55.0

≤1.0

2.80~3.30

0.30~0.70

0.75~1.15

Balance

High purity

0.02~0.06

17.0~21.0

50.0~55.0

≤1.0

2.80~3.30

0.30~0.70

0.75~1.15

Balance

Type

Nb

B

Mg

Mn

Si

P

S

Cu

Ca

Standard

4.75~5.50

0.006

0.01

0.35

0.35

0.015

0.015

0.30

0.01

High quality

5.00~5.50

0.006

0.01

0.35

0.35

0.015

0.015

0.30

0.01

High purity

5.00~5.50

0.006

0.005

0.35

0.35

0.015

0.015

0.30

0.005

Type

Bi

Sn

Pb

Ag

Se

Te

Tl

N

O

Standard

0.0005

0.0003

High quality

0.001

0.005

0.001

0.001

0.0003

0.01

0.01

High purity

0.00003

0.005

0.001

0.001

0.0003

0.00005

0.0001

0.01

0.005

The specific heat capacity of GH4169 is shown in table 2-2.

Heat treatment system of GH4169

The alloy has different heat treatment systems to control the grain size and temperature δ The morphology, distribution and quantity of the phases are used to obtain different levels of mechanical properties. There are two kinds of alloy heat treatment systems:
Ⅰ:(1010~1065)℃ ± 10 ℃, 1H, oil cooling, air cooling or water cooling + 720 ℃ ± 5 ℃ for 8h, cooled to 620 ℃ at 50 ℃ / h ± 5 ℃, 8h, air cooling.
The grain size of the material treated by this system is coarsened, and there is no grain boundary or intragrain δ However, it is beneficial to improve the impact property and resist low temperature hydrogen embrittlement.
Ⅱ:(950~980)℃ ± 10 ℃, 1H, oil cooling, air cooling or water cooling + 720 ℃ ± 5 ℃ for 8h, cooled to 620 ℃ at 50 ℃ / h ± 5 ℃, 8h, air cooling.
After being dealt with by this system, the δ It can improve the strength and impact properties of the material. This system is also called direct aging heat treatment system.

Varieties, specifications and status of GH4169

It can supply die forgings (plate, plate integral forgings), cakes, rings, bars (forged bars, rolled bars, cold drawn bars), plates, wires, belts, tubes, fasteners of different shapes and sizes, elastic elements, etc. The delivery status shall be agreed by the supplier and the demander. The wire shall be delivered in pallets in the agreed delivery state.

Melting and casting process of GH4169

The smelting process of the alloy can be divided into three types: Vacuum Induction Electroslag Remelting; Vacuum induction and vacuum arc remelting; Vacuum induction plus electroslag remelting plus vacuum arc remelting. According to the use requirements of the parts, the required smelting process can be selected to meet the application requirements.

Application and special requirements of GH4169

Manufacture all kinds of stationary and rotating parts in aviation and aerospace engines, such as disks, rings, casings, shafts, blades, fasteners, elastic elements, gas ducts, sealing elements and welded structural parts; Manufacturing all kinds of elastic elements and grids for industrial application; Manufacture parts and other parts for petroleum and chemical applications.
In recent years, on the basis of deepening the research and expanding the application of the alloy, in order to improve the quality and reduce the cost, many processes have been developed: helium cooling process is used in vacuum arc remelting to effectively reduce the niobium segregation; Spray forming process is used to produce rings, which can reduce the cost and shorten the production cycle; Superplastic forming process is adopted to expand the production range of products.

Physical and chemical properties of GH4169

Thermal properties of GH4169
The melting temperature range of GH4169 is 1260 ~ 1320 ℃
The thermal conductivity of GH4169 is shown in table 2-1:

θ/℃

11

100

200

300

400

500

600

700

800

900

1000

λ/(W/(m•C))

13.4

14.7

15.7

17.8

18.3

19.6

21.2

22.8

23.6

27.6

30.4

Table 2-2

θ/℃

300

400

500

600

700

800

900

1000

c/(J/(kg•C))

481.4

493.9

514.8

539.0

573.4

615.3

657.2

707.4

The coefficient of linear expansion of GH4169 is shown in table 2-3:

θ/℃

20~100

20~200

20~300

20~400

20~500

20~600

20~700

20~800

20~900

20~1000

α/10-6C-1

11.8

13.0

13.5

14.1

14.4

14.8

15.4

17.0

18.4

18.7

Density of GH4169

  • ρ= 8.24g/cm3 

Magnetic energy type of GH4169
The alloy is nonmagnetic.
Chemical properties of GH4169
The oxidation rate of GH4169 after 100 h in air is shown in table 2-4:

θ/℃

600

700

800

900

1000

Oxidation rate/(g/(m3•h))

0.0176

0.0277

0.0351

0.0961

0.1620

Process performance and requirements of GH4169

Performance of GH4169
Because of the high content of niobium in GH4169 alloy, the segregation of niobium is directly related to the metallurgical process. The melting speed of ESR and vacuum arc melting and the quality of electrode rod directly affect the quality of material. The melting rate is fast and niobium rich black spots have been formed; If the melting rate is slow, niobium poor white spots will be formed; The poor surface quality and internal cracks of the electrode rod are easy to cause the formation of white spots. Therefore, improving the quality of the electrode rod, controlling the melting rate and increasing the solidification rate of the ingot are the key factors in the smelting process. In order to avoid heavy element segregation in ingot, the diameter of ingot used up to now is less than 508mm. The homogenization process must ensure the complete dissolution of L phase in ingot. The time for two-stage homogenization of ingot and secondary homogenization of intermediate billet depends on the diameter of ingot and intermediate billet. The control of homogenization process is directly related to the segregation of niobium in the material.
At present, the homogenization process of 1160 ℃, 20h + 1180 ℃, 44h is not enouGH to eliminate the segregation in the center of ingot.
Therefore, the following process is recommended:

  • 1. 1150℃~1160℃,20h~30h+1180℃~1190℃,110h~130h; 
  • 2. 1160℃,24h+1200℃,70h.

The homogenized alloy has good hot workability. The heating temperature of ingot should not exceed 1120 ℃. The forging process of forgings shall be determined according to the service conditions and application requirements of forgings and the conditions of the manufacturer. The intermediate annealing temperature and temperature must be determined according to the required microstructure and properties of military parts in the process of bloom and forging production. Generally, the forging temperature should be controlled between 930 ℃ and 950 ℃. The forging temperature and deformation degree of the forgings are shown in the table:


Types of forgings

First forging

First forging

Second forging

Second forging

Grain size / grade

Grain size / grade

Heating temperature/℃

Deformation/%

Heating temperature/℃

Deformation/%

Basic grain

Individual large grains

Ordinary

1065~1090

1040~1065

4~6

Allow

High strength

1040~1065

1010~1040

30~50

8

≥2

Direct prescription

995~1025

>50

970~995

>50

10

≥2

The surface of workpiece must be cleaned before and during heating to keep the surface clean. If the heating environment contains sulfur, phosphorus, lead or other low melting point metals, GH4169 alloy will become brittle. Impurities come from paint, chalk, lubricating oil, water, fuel, etc. The sulfur content of fuel should be low, such as the impurity content of liquefied gas and natural gas should be less than 0.1%, the sulfur content of city gas should be less than 0.25g/m3, and the sulfur content of petroleum gas should be less than 0.5%.
Preheating of GH4169
The heating electric furnace should have more accurate temperature control ability, and the furnace gas should be neutral or weakly alkaline, so the composition of the furnace gas should not fluctuate in the oxidizability and reducibility.
Hot working of GH4169
The suitable hot working temperature of GH4169 alloy is 1120-900 ℃, and the cooling method can be water quenching or other rapid cooling methods. After hot working, the alloy should be annealed in time to ensure its properties. During hot working, the material should be heated to the upper limit of processing temperature. In order to ensure the plasticity during processing, the final processing temperature when the deformation reaches 20% should not be lower than 960 ℃.
Cold working of GH4169
Cold working should be carried out after solution treatment. The work hardening rate of GH4169 is higher than that of austenitic stainless steel. Therefore, the processing equipment should be adjusted accordingly, and there should be an intermediate annealing process in the process of cold working.
Heat treatment of GH4169
Different solution treatment and aging treatment process can get different material properties. because γ” The diffusion rate of phase is low, so the mechanical properties of GH4169 alloy can be obtained by long time aging treatment.
Grinding of GH4169
The oxide near the weld of GH4169 workpiece is more difficult to remove than that of stainless steel, so it needs to be polished with fine sand belt. Before pickling in the mixed acid of nitric acid and hydrofluoric acid, the oxide should also be removed with sandpaper or salt bath pretreatment.
Machining of GH4169
The machining of GH4169 needs to be carried out after solution treatment, and the work hardening of the material should be considered. Different from austenitic stainless steel, GH4169 is suitable for low surface cutting speed.
Welding of GH4169
The precipitation hardening GH4169 alloy is suitable for welding and has no tendency of cracking after welding. Weldability, machinability and high strength are the advantages of this material.
GH4169 is suitable for arc welding, plasma welding, etc. Before welding, the surface of the material shall be clean, free of oil and powder, and the briGHt metal shall be polished within 25 mm around the weld.
Recommended welding materials for GH4169:

  • GTAW/GMAW 
  • Nicrofer S 5219 
  • W.-Nr. 2.4667 
  • SG-NiCr19NbMoTi 
  • AWS A 5.14 ERNiFeCr-2 
  • BS 2901 Part 5: NA 51 
  • Function test of GH4169

The turbine disk, oil rejection disk, integral rotor, shaft, fastener and other parts made of the alloy have passed the over rotation, fracture and low cycle fatigue tests in the engine parts and components test according to the engine model specifications; It has passed the long-term (life-span) test and fliGHt test of high altitude platform, and met the requirements of design and application.
Suggestions on the use of GH4169
It is recommended to use, and the stress concentration exceeding the bearing capacity of the material must be avoided.

GH2747

GH2747 is a Fe Ni Cr Based precipitation hardening deformation superalloy. It is used in the solid solution state. The long-term service temperature is 1100-1250 ℃, and the short-term service temperature can reach 1300 ℃. The alloy has high strength, good structure stability, good oxidation resistance and corrosion resistance.
Ingredients:

C

Cr

Ni

Fe

Mo

Si

Mn

P

S

Al

V

W

Ce

≤0.10

15-17

44-46

Balance

≤1.0

≤1.0

≤0.02

≤0.025

2.9-3.9

≤0.03

Performance:

Density g/cm³

Thermal conductivity /w/(m.k)

    100~900℃

Coefficient of linear expansion /(10-6/k)

    20~800℃

8.26

10.5-24.3

17.07

Temperature 0/℃

20

500

600

700

800

Elastic modulus E/GPa

218

177

159

146

128

Type

Heat treatment

Temperature 0/°C

Tensile strength Σb\MPa

Elongation A/%

Reduction of area Z/%≥

Hot bar

Standard heat treatment

20

550

15

20

1000

40

30

30

Cold rolled sheet

Standard heat treatment

20

600

30

Welding:
The alloy has satisfactory welding process performance, and can be well welded by all welding methods. The welding effect of argon arc welding, spot welding, roll welding and electron beam welding is excellent. When welding with different materials, the base metal wire can be used as filler material, and the same type of alloy can be used as filler material.
Application fields:
GH2747 is suitable for making anti-oxidation parts in engine combustion chamber and afterburner, various heat-resistant parts for industrial boilers, transmission devices, thermowells, etc. Such as petrochemical, nuclear energy, metallurgy and other fields with high temperature oxidation device parts.

GH5188

GH5188 is a solution strengthened cobalt base superalloy. Adding 14% tungsten solution strengthening can make the alloy have excellent high temperature thermal strength. Adding high content of chromium and trace lanthanum can make the alloy have good high temperature oxidation resistance and satisfactory forming and welding properties, It is suitable for manufacturing aeroengine parts which require high strength below 980 ℃ and oxidation resistance below 1100 ℃. It can also be used in space engine and space shuttle. Can produce and supply a variety of deformation products, such as sheet, plate, strip, bar, forging, wire and precision castings.
Application field: manufacturing high temperature components of aero engine combustor flame tube, guide vane, gas turbine and missile.

MP35N

Mp35N is an age hardening nickel cobalt alloy with a unique combination of properties – ultra-high strength, touGHness, ductility and excellent corrosion resistance. Mp35n has corrosion resistance in hydrogen sulfide, brine and other chloride solutions. It also has excellent resistance to crevice corrosion and stress corrosion cracking in seawater and other harsh environments. It is suitable for environment with high strength, high modulus and good corrosion resistance. Applications of this alloy also include medical devices and dental products
Grade of Mp35N:

National standard

American Standard

German standard

Japanese standard

mp35n

R30035

2.4999

mp35n

The composition of mp35n is as follows:

Element

C

P

Si

Ni

Co

Cr

Mo

Ti

Fe

Mn

S

Max

0.025

0.015

0.15

37

Balance

21

10.5

1

1

0.15

0.01

Min

33

19

9

Performance of mp35n:

Density

Melting point

Expansion coefficient

Modulus of elasticity

Tensile strength

8.43 g/cm³

1440°C

12.8 μm/m °C

234 kN/mm²

1900MPa

The executive standard of mp35n is as follows:

  • AMS5758
  • AMS5844
  • AMS5845
  • ANSI/ASTM F562

GH3536

GH3536 is a Fe Ni Cr based solution strengthened wrouGHt superalloy, which has medium holding time and creep strength at 900 ℃. It has good oxidation and corrosion resistance, good cold and hot working formability and weldability. It is suitable for making aero-engine combustion chamber and other parts under 900 ℃ for long-term use and high-temperature parts under 1080 ℃ for short-term use. There are mainly plate, strip, tube, bar, forging and casting.
Corresponding brands in different countries:

American Standard

French Standard

German standard

British Standard

National standard

NO6002 /HastelloyX

NC22FeD

NiCr22FeMo

Nimonic PE13

GH3536

Chemical composition:

Element

C

Cr

Ni

W

Mo

Fe

B

S

Mn

Si

P

Cu

Ti

Al

Co

Min

0.05

20.5

0.2

8

17

0.5

Max

0.15

23

Balance

1

10

20

0.01

0.015

1

1

0.015

0.5

0.15

0.5

2.5

Performance parameter:

Density g/cm³

Magnetic

Tensile strength Σb\MPa
    ≥

Elongation A/%
    ≥

8.28

No

690

30

Thermal conductivity /w/(m.k)
    100~900℃

Resistivity 
    ℃)/(Ω.mm2/m)
    20~900℃

Specific heat capacity 
    ℃)/kg/(kj.k)℃
    100~900℃

Coefficient of linear expansion 
    /(10-6/k)
    20~900℃

13.38-33.44

1.18-1.29

0.3726-0.561

16.1

Application:

  • Industrial and aviation steam turbines (combustors, rectifiers, structural covers)
  • Industrial furnace parts, backup roll, grid plate, ribbon and radiant tube
  • Spiral tube in petrochemical furnace
  • High temperature gas cooled nuclear reactor

GH3039

GH3039 is a single-phase austenite solid solution strengthening alloy 800 It has moderate thermal strength and good thermal fatigue performance below ℃, one thousand The oxidation resistance is good below ℃. It has stable microstructure, good cold formability and weldability. Suitable for 800 and fifty Parts of combustion chamber and afterburner used for a long time below ℃. The alloy can be used for plate, bar, wire, tube and forging.
1.  GH3039 Material grade: GH3039 (GH39)
2.  GH3039 Technical standards of materials :

  • GJB 1952-1994 specification for cold rolled high temperature alloy sheet for aviation
  • GJB 2297-1995 specification for cold drawn (rolled) seamless tubes of superalloy for aviation
  • GJB 2612-1996 specification for cold drawn Superalloys for aviation
  • GJB 3165-1998 specification for hot rolled and forged high temperature alloy bars for aircraft load bearing parts
  • GJB 3317-1998 specification for hot rolled superalloy plates for aviation
  • GJB 3318-1998 specification for cold rolled high temperature alloy strip for aviation
  • GB / t15062-1994 general purpose superalloy pipe

GH3039 Chemical composition: see table 1-1 .  

Table 1-1  % 

C≤

Si≤

Mn≤

P≤

S≤

Cr≥

Ni≥

Mo≥

Cu≤

0.08

0.80

0.40

0.020

0.-12

19.0-22.0

allowance

1.80-2.30

other

N≤

Al≤

Ti≤

Fe≤

Co≤

V≤

W≤

Nb≤

0.35-0.75

0.35-0.75

3

0.90-1.30

Note:

  • The alloy is allowed to have Ce.
  • In alloy ω (Cu)=0.20%. 

GH3039 Heat treatment system: solution treatment of hot rolled and cold rolled sheet and strip: 1350 ~ 1490 °C, air cooling. Solid solution treatment of bar and tube: 1350 ~ 1380 Air cooling or water cooling.
GH3039 Of Variety specification and supply status: it can supply various specifications of hot rolled plate, cold rolled plate, strip, bar, wire, pipe and forging. Plate, strip and pipe are delivered after solution treatment and pickling. Wire is supplied in cold working or solution state, and bar is delivered without heat treatment.
GH3039 Of Smelting and casting process: electric arc furnace melting, electric arc furnace or non vacuum induction furnace plus electroslag remelting or vacuum arc remelting, and vacuum induction furnace plus electroslag or vacuum arc remelting processes are adopted.
GH3039 Of Application Overview and special requirements: the aeroengine combustion chamber and afterburner parts made of this alloy have good performance after long-term production and service test.
GH3039 Of Physical and chemical properties:
GH3039 Of Thermal properties:  
(1).  GH3039 Of Thermal conductivity: see table 2-1 .
Table 2-1

θ/ ℃

100

200

300

400

500

600

700

800

900

λ/( W/(m·℃))

13.8

15.5

17.2

18.8

20.5

21.8

23.4

25.1

26.8

(2).  GH3039 Of Specific heat capacity: see table 2-2 .  
Table 2-2

θ/ ℃

150

200

300

400

500

600

700

800

c/(J/(kg.K))

544

574

636

645

762

779

921

147

(3).  GH3039 Of Coefficient of linear expansion: see table 2-3 .
Table 2-3

θ/ ℃

20-100

20-200

20-300

20-400

20-500

20-600

20-700

20-800

20-900

20-1000

α/ ten -6 ℃ -1

11.5

12.4

13.2

13.5

13.8

14.3

14.9

15.3

15.8

16.4

2.  GH3039 Of Density:   ρ =8.3g/cm three .
3.  GH3039 Of Electrical properties: room temperature resistivity ρ =1.18 × ten -6 Ω· m .
4.  GH3039 Of Magnetic properties: the alloy has no magnetism.  
5.  GH3039 Of Chemical properties: GH3039 oxidation resistance:     
(1)
 .  GH3039 In air medium 100h Oxidation rate after test: see table 2-4 .

θ/ ℃

900

100

1100

1200

Oxidation rate / (g / (m) two ·   h))

0.074

0.251

0.535

1.061

Table 2-5

θ/ ℃

900

1000

1100

Oxidation depth along grain boundary / mm

0.020

0.052

0.068

GH3030

Chemical composition

alloy

%

iron

chromium

phosphorus

copper

nickel

aluminum

titanium

carbon

manganese

silicon

vanadium

sulfur

GH3030

Min

19

Balance

  0.15

0.10

Max

1.0

22

0.015

0.20

0.15

0.35

0.12

0.70

0.80

0.50

0.02

GH3030 Its physical properties are as follows:

Density

8.4 g/cm3

melting point

1374-1420 ℃

GH3030 In the solid solution state, the mechanical properties of the alloy at room temperature are as follows:

Alloy state

tensile strength
   σ b (Mpa)

Elongation
  A5 %

GH3030

785

≥35

This alloy has the following characteristics:

80Ni-20Cr

Solution strengthened superalloy has simple chemical composition, satisfactory thermal strength and high plasticity below 800 ℃, and good oxidation resistance, thermal fatigue, cold stamping and welding process properties. After solution treatment, the alloy is single-phase austenite with stable structure during service.  

Metallographic structure of GH3030:

GH3030 alloy is a single-phase austenite structure with a small amount of tic and Ti (CN).  

The application scope of GH3030 is as follows:

1. It is mainly used for combustion chamber of turbine engine working below 800 ℃

2. Other high temperature parts that require oxidation resistance but bear little load below 1100 ℃

3. It is used to make movable burning frame in enamel furnace

GH3044

GH3044 alloy is a solid solution strengthened Ni based oxidation resistant alloy 900 It has high plasticity and medium thermal strength, excellent oxidation resistance and good stamping and welding process performance below 900 ℃. It is suitable for manufacturing aero-engine main combustion chamber and afterburner parts, heat shield, guide vane and so on.

Technical standard of GH3044

Forging

GB/T14997,GB/T14998,GJB3020

Bar

GB/T14994,GB/T1493,HB5189,GJB3165

Plate / belt

GB/T14995,GB/T14996,GJB3317,GJB1952,GJB3318

Silk

GB/T5249,GJB2612

Variety and specification of GH3044: Plate, bar, ring forging, finished products negotiation supply.

Chemical constituents of GH3044

C

Mn

Si

P

S

Ni

≤0.10

≤0.50

≤0.80

≤0.013

≤0.013

Balance

Cr

Mo

W

Al

Ti

Fe

23.5-26.5

≤1.5

13.0-16.0

≤0.5

0.3-0.7

≤4.0

Physical properties of GH3044

Density: 8.89 g / m3

Melting point: 1352 ℃ – 1375 ℃

Magnetic properties: None  

Welding properties of GH3044

1. It can be welded by argon arc welding, spot welding, seam welding and brazing.

2. In argon arc welding, the fluidity of molten pool is poor, but the tendency of crack is small. In contact welding, it is easy to form bonding line extension and shrinkage cavity in the core. Generally, larger electrode pressure and lower welding speed should be adopted.  

Heat treatment process of GH3044 parts

1. The intermediate heat treatment temperature is 1140 ℃ ± 10 ℃ for 3-5min, air cooling.

2. * the final heat treatment temperature is determined according to the working conditions of the parts. For parts with good thermal fatigue performance, solid solution is conducted at 1150 ℃ for 3-5min, and air cooling is conducted;

3. For parts with high thermal strength, solid solution shall be conducted at 1200 ℃ for 3-5min, and air cooling shall be conducted.  

Surface treatment technology of GH3044

Parts working at high temperature can be effectively protected by W-2 enamel coating

Application fields of GH3044

  • Main combustion chamber and afterburner of Aeroengine
  • Welding structure of Aeroengine
  • Engine mounting edge and duct
  • Guide vane components

GH141

GH141 is a Precipitation Hardening Nickel Base Superalloy with high tensile and creep rupture strength and good oxidation resistance in the range of 650-950 ℃. Due to the high content of Al, Ti and Mo in the alloy, it is difficult to open the ingot. However, the deformed material has good plasticity, which can be cold formed or welded in the annealed state. The strain aging cracks are easy to occur in the heat treatment of welded parts. The alloy varieties include thin plate, strip, wire, disc, ring, forging, bar, precision casting, etc. it is suitable for manufacturing high-temperature parts of aviation and aerospace engines that require high strength below 870 ℃ and oxidation resistance below 980 ℃.  

GH141 material Of Brand name:

  • GH4141  

GH141 is similar Of Brand name:

  • UNS N07041,Rene′41,R41,Carpenter41,PYROMET41,UNITEMP41,   Hynessalloyr41, j1610 (USA).  

Technical standard of GH141 material:

  • GH141 alloy bars (Q / 3b 4060-1992)  
  • Q / 3b 4063-1992 cold rolled strip of GH141 alloy  
  • Q / 5B 4027-1992 “GH141 alloy round cake, ring blank and ring parts”  
  • GH141 alloy bars for high temperature fasteners (Q / 6S 1033-1992)  
  • Fugaoxin 84-13 technical conditions for GH141 alloy bars for Aerospace  
  • GH141 Of Variety specification and supply status

It can provide various specifications of round cake, ring blank, ring parts, thin plate, strip, bar, forging and precision casting, etc. Plates are delivered in solution state, bars and forgings are delivered without heat treatment.  

GH141 Of Melting and casting process

Vacuum induction melting, vacuum induction melting plus electroslag remelting or vacuum arc remelting are adopted.  

GH141 Of Application Overview and special requirements

The alloy is widely used in the manufacture of high temperature load-bearing parts of aerospace engines, such as guide vane, combustion chamber, turbine, high-temperature load-bearing parts of guide device, shaft, disc, blade and fastener, etc. strain aging crack of plate welding parts during heat treatment can be solved by over aging treatment before welding or by controlling cooling rate after solution treatment before welding, Standard heat treatment shall be conducted after welding.  

Thermal properties of GH141  

GH141 Of Melting temperature range: 1316~1371℃.  

GH141 density: ρ= 8.27g/cm3.  

Microstructure of GH141 alloy

Microstructure removal of alloy in standard heat treatment state γ In addition to the matrix, there are γ′.  M6C, M23C6 and MC were found after long-term aging μ Phase precipitation.  

GH141 process performance and requirements  

Formability of GH141

High temperature homogenization treatment should be carried out before forging GH141 steel ingot. The forging heating temperature is 1160 ~ 1180 ℃, and the final forging temperature is not less than 1000 ℃. The heating temperature of slab rolling is 1140 ~ 1160 ℃, and the final rolling temperature is not lower than 1060 ℃. The heating temperature of sheet rolling is 1140 ~ 1160 ℃, and the final rolling temperature is not lower than 800 ℃.  

Spinning performance of GH141

The plate has good spinnability while keeping fine grain and low hardness. Reduction of area at room temperature φ(%) Calculate the thinning φ max(%)= φ(%)/[ 0.17+ φ(%)].

Welding performance of GH141  

GH141 alloy can be used for fusion welding, diffusion welding, brazing and friction welding. Both electron beam welding and argon arc welding can be used for fusion welding. In order to reduce this tendency, slow solution annealing should be carried out before welding, i.e. 1080 ℃, and then cooled to 650 ℃ at 22 ℃ / min; Another method is to carry out over aging treatment before welding, that is, 1080 ℃, 30min, 1.7 ~ 4.4 ℃ / min to 980, 4h, 1.7 ~ 4.4 ℃ / min to 870 ℃, 4h, and then 1.7 ~ 4.4 ℃ / min to 760 ℃, 16h, air cooling [1,16 ~ 19]. After welding, when the welding stress is relieved and the properties are restored, the aging hardening temperature range should be quickly heated to eliminate the tendency of strain aging cracking. Using base metal with fine grain and low impurity content can eliminate mechanical work hardening, and low welding line energy can also reduce the tendency of strain aging cracking.

Heat treatment process of GH141 parts  

When GH141 works at lower temperature and requires high tensile strength and fatigue performance of parts, 1080 ℃, air cooling + 760 ℃, 16h air cooling is recommended.  

When GH141 works at high temperature and requires high thermal strength, the appropriate heat treatment specification is 1180 ℃, air cooling + 900 ℃, 4h, air cooling.  

GH141 is recommended to use 1120 ℃, 30min, air cooling + 900 ℃, 4H for annular parts and other parts requiring welding.

Nickel base wrought superalloy

NIMONIC80A

Nimonic 80A is formed by adding Al and Ti in Ni Cr matrix γ′ The phase dispersion strengthened superalloy has good creep resistance and oxidation resistance at 700-800 ℃ and 650-850 ℃, except for sliGHtly higher aluminum content. The alloy has good cold and hot working properties. It mainly supplies hot-rolled bar, cold drawn bar, hot-rolled plate, cold-rolled sheet, strip and annular parts, etc., and is used for manufacturing engine rotor blade, guide vane support, bolt, blade lock plate and other parts.  
Nimonic 80A material grade: Nimonic 80A.  
Similar brand of Nimonic 80A: GH80A (China).  
Technical standard of Nimonic 80A material
The chemical composition of Nimonic 80A is shown in Table 1-1.  
Table 1-1  %


C

Cr

Ni

Al

Ti

0.04~0.10

18.0~21.0

more than

1.00~1.80

1.8~2.7

Co

Fe

B

Mn

Si

P

S

Ag

Bi

Cu

Pb

two

one .50

0.zero0 eiGHt

0.40

0.eiGHt0

0.zero two0

0.zero one five

0.zero00 five

0.zero00 one

0.20

0.zero0 two

Note: B It is allowed to add trace elements of CE, Zr and Mg according to the calculated amount.  

The bar for blade of Nimonic 80A heat treatment system is 1080 ℃ ± 10 ℃, 8h, air cooling + 700 ℃ ± 5 ℃, 16h, air cooling. Hot rolled, forged and cold drawn bars: as specified in table 1-2. Rolling ring: (1050 ~ 1080 ℃) ± 10 ℃, ≤ 2h, water cooling + 750 ℃ ± 5 ℃ (or + 700 ℃) ± 5 ℃), 4H (or 16h), air cooling. Hot rolled sheet, cold rolled sheet and strip: as supplied + 750 ℃ ± 10 ℃, 4 h, air cooling.  
Table 1-2

Material type

Solution treatment system

prescription system

Hot rolled (or forged) bars for hot working

1080℃ ± 10 ℃, 8h, air cooling

700℃ ± 5 ℃, 16h, air cooling or 750 ℃ ± 5 ℃, 4 h, air cooling

Hot rolling for hot working  
(or forged) bar

According to the system ① or ②  
①1080℃ ± 10 ℃, the holding time shall be as specified in table 1-3, oil cooling or water cooling or air cooling( Normal condition, D ≥ 40mm, oil cooled)  
②1080℃ ± 10 ℃, holding time according to table 1-3, air cooling + 1080 ℃ ± 10 ℃ for 30min, water cooling

Cold drawn bar

1080℃ ± 10 ℃ for water cooling or air cooling according to table 1-4.

Table 1-3

Diameter / mm

Holding time / h

Diameter / mm

Holding time / h

≤3

1

>6~12.5

4

>3~6

2

>12.5

8

Nimonic 80A specification and supply status: hot rolled bars for blades with diameter of d20-55mm, hot-rolled or forged bars with diameter ≤ 300 mm are supplied. Cold drawn bar is supplied with round bar with diameter of 8-45mm and hexagonal bar with diameter of inscribed circle of d8-36mm. Supply rolled parts with outer diameter of 1000mm, inner diameter of 900mm and height of 130mm. Supply hot rolled sheet with thickness ≤ 9.5mm, cold rolled sheet with thickness ≤ 4.0mm and cold rolled strip with thickness ≤ 0.8mm. Hot rolled bars for blades are supplied without heat treatment, and their surfaces shall be completely polished or polished. Hot rolled bars for machining are supplied in the state of solution treatment and scale removal. Cold drawn bars for upsetting shall be supplied in cold drawn and polished condition, cold drawn bars for machining shall be supplied in cold drawn solution treated and oxide scale removed state, and hot working bars shall be supplied in manufacturing state with oxide scale removed (for bars used in forging plant, the surface rouGHness shall not be less than 3.2 μ m). Rolled rings are supplied in solution treated and rouGH machined condition. Hot rolled sheet, cold rolled sheet and strip are supplied after softening treatment, alkaline pickling, trimming and leveling or straiGHtening.  
Melting and casting process of Nimonic 80A

The vacuum induction melting and electroslag remelting process is adopted for the bar and plate of blade. Induction melting plus electroslag remelting, vacuum induction melting plus vacuum arc remelting or vacuum induction melting plus electroslag remelting are adopted for rolling ring parts and hot rolled, forged and cold drawn bars.  
Application and special requirements of Nimonic 80A

The alloy is mainly used for engine rotor blade, guide vane support, fan-shaped parts installation ring, bolt, blade lock plate and other parts.  
Physical and chemical properties of Nimonic 80A  
Thermal properties of Nimonic 80A  
Nimonic80A Of Melting temperature range: melting point 1405 ℃.  
Nimonic80A Of The thermal conductivity is shown in table 2-1.  
Table 2-1

θ/ ℃

100

200

300

400

500

600

700

800

900

λ/( W/(m·℃))

20.11

13.83

15.48

16.75

18.39

20.93

23.48

25.57

27.66

Nimonic80A Of The coefficient of linear expansion is shown in table 2-2.  
Nimonic80A Of Density: ρ= 8.15g/cm3.  
Table 2-2

θ/ ℃

16~100

16~200

16~300

16~400

16~500

16~600

16~700

α/ 10-6℃-1

20.18

20.86

13.69

14.08

14.50

14.94

15.36

Nimonic80A Of Electrical properties: room temperature ρ= one .2 three × 10-6 Ω. m.  
Nimonic80A Of Magnetic property: no magnetism.  
Nimonic80A Of Chemical properties  
The oxidation rate of Nimonic 80A in air for 100h is shown in table 2-3.  
Table 2-3

θ/ ℃

700

700 and fifty

800

Oxidation rate / (g / (M2 · h))

0.037

0.041

0.047

Mechanical properties of Nimonic 80A  
The specified properties of Nimonic 80A turbine blade bar are shown in table 3-1.  
Table 3-1

technical standard

Sample series logarithm

Persistent performance

θ/ ℃

σ/ MPa

Break time / h

Single value

average value

Range value (Rmax) = (f)·( )

WS9-7009-1996

three

750

340

≥23

≥32

≤0.6 × Actual average

Organizational structure of Nimonic 80A  
Phase transition temperature of Nimonic 80A  
Time temperature microstructure transition curve of Nimonic 80A  
Microstructure of Nimonic 80A alloy blade blank treated by different heat treatment specifications: 1080 ℃ ± 10 ℃, 8h, air cooling treatment: at 1080 ℃ γ′ Phase and some M7C3 and M23C6 type grain boundary carbides dissolve into the solid solution. During cooling, M7C3 and M23C6 type chromium rich carbides are formed at grain boundaries. M7C3 precipitates above 1000 ℃ and transforms into M23C6 at lower temperature. M23C6 precipitates at 750-1000 ℃ and can nucleate independently and form grain boundary carbides. So at 1080 ℃ ± After air cooling at 10 ℃ for 8 h, there are discontinuous M7C3 and M23C6 on the grain boundary γ′ XianGHe MC.  
1080℃ ± 10 ℃, 8h, air cooling + 700 ℃ ± 5 ℃, 16 h, air cooling treatment: the alloy was treated at 700 ℃ on the basis of solid solution structure ± After aging at 5 ℃ for 16 h, M7C3 on the grain boundary continues to transform into M23C6, so continuous M23C6 precipitates on the grain boundary γ′ The phases also grow into spheroidal particles [4].  
Technical performance and requirements of Nimonic 80A  
Formability of Nimonic 80A  
Nimonic 80A forging alloy has good forging properties. The ingot heating temperature is 1120 ~ 1150 ℃, and the opening forging temperature is not less than 1000 ℃. The stop forging temperature shall not be lower than 950 ℃.  
The heating temperature of Nimonic 80A hot rolled plate is 1120-1150 ℃, and the stop rolling temperature is not lower than 930 ℃.
The forging turbine blade blank of Nimonic 80A turbine blade shall be sprayed with protective lubricant according to the specified process requirements, and can be heated in furnace after drying. The blank of parts is heated in the electric furnace, and the charging temperature is 800 ℃ ± 20 ℃, holding for 60min, heating temperature 1090 ℃ ± The forging temperature is 1090 ℃ and the stop forging temperature is 950 ℃. Solid solution treatment should be carried out in the intermediate process of blank forging, and the heating temperature should be 1130 ℃ ± 10 ℃, heat preservation for 60min, air cooling. After sand blowing, the protective lubricant shall be sprayed according to the specified process requirements, and the furnace shall be heated after drying. The blank of the parts shall be furnace loaded, heated and insulated according to the above provisions, and the final forging shall be carried out on the crank press, and the die chamber shall be lubricated with molybdenum disulfide before forging.  
Nimonic 80A alloy with weldability can be used for automatic butt argon arc welding and seam welding.  
See Table 5-1 for automatic TIG welding (butt joint) specification of Nimonic 80A without welding wire.  
Table 5-1

Thickness / mm

State before welding

Current / A

Voltage / V

Welding speed / (M / min)

Backing plate

Gas flow rate / (L / min)

Back gas flow / (L / min)

Tungsten electrode diameter / mm

Nozzle diameter / mm

Groove width

Groove depth

one .2

Soft state

55

10~12

0.21

4.57

1 .5

10~15

5~6

2~4

10~14

Note: before welding, the sample shall be polished with sand cloth and cleaned with acetone. The plate with thickness ≤ 1.2mm is not filled with welding wire, and it is formed by welding at one time.  
The seam welding specification of Nimonic 80A is shown in table 5-2.  
Table 5-1

Thickness / mm

State before welding

Disc width / mm

Power level

Voltage / V

Pulse lattice

Rest lattice

Caloric lattice

Welding speed / (M / min)

Electrode pressure / n

upper

lower

one .2

Soft state

0.5

6.5

3

390

15

15

5~8

0.15

8728

The mechanical properties of Nimonic 80A welded joint are shown in table 5-3.  
Table 5-3

welding method

joint style

Thickness / mm

State before welding

Post weld condition

Joint strength

Strength coefficient /%

θ/ ℃

σ b/MPa

Automatic argon arc welding

Docking

1.2

Soft state

1080℃ ± 10 ℃, 8h, air cooling + 750 ℃ ± 5 ℃, 4 h, air cooling

20

1138~1236

100

Seam welding

Lap joint

1.2

Soft state

20

950~1080

85

Note: the data in this table refer to the data processing results of tensile test for two batches of plates and two samples for each batch.  
The heat treatment process of Nimonic 80A parts is carried out according to the heat treatment system of corresponding material technical standards. For stamping parts of sheet and strip, intermediate vacuum annealing should be carried out after each forming, 1060 ℃ ± 10 ℃, 10 min, argon fan cooling, heat treatment of parts in vacuum furnace aging treatment, 750 ℃ ± At 10 ℃ for 4 h, argon fan was used for cooling. For the local work hardening of the blade during the manufacturing process after solution treatment (before aging), argon or hydrogen protection surface annealing shall be carried out according to the specified requirements, and the annealing temperature is 1070 ~ 1090 ℃.  
Surface treatment of Nimonic 80A
The cutting and grinding properties of Nimonic 80A show good machinability and good machinability under complete heat treatment.
Table 1-4

Diameter or smaller section size / mm

Holding time / min

Diameter or smaller section size / mm

Holding time / min

≤15

15~30

>15~25

30~45

NIMONIC90

Nimonic 90 is an age hardening nickel base wrought superalloy with high content of cobalt and various strengthening elements. The alloy has high tensile strength and creep resistance, good oxidation resistance and corrosion resistance, high fatigue strength and good formability and weldability under the alternating action of hot and cold at 815 ~ 870 ℃. Mainly supply hot-rolled and cold drawn bar, cold-rolled sheet, strip and cold drawn wire. It is used for turbine disk, blade, high temperature fastener, clamp, seal ring and elastic element of turbine engine.  
Material grade of Nimonic 90: Nimonic 90.  
Similar brand of Nimonic 90: GH90 (China).  
Technical standard of Nimonic 90 material  
The chemical composition of Nimonic 90 is shown in Table 1-1.  
Table 1-1 %

C

Cr

Ni

Co

Al

Ti

Mn

Si

P

S

Ag

Pb

Bi

B

Cu

Fe

Zr

≤0.13

18.0~21.0

Allowance

15.0~21.0

1.0~2.0

2.0~3.0

0.4

0.8

0.020

0.015

0.0005

0.0020

0.0001

0.0020

0.2

1.5

0.15

Note: wire material regulations ω( pb)≤0.0010%.  
Heat treatment system of Nimonic 90  
Nimonic 90 cold drawn bar: 1080 ℃ ± 10 ℃, the holding time is shown in table 1-2, air cooling or water cooling + 750 ℃ ± 10 ℃, 4 h, air cooling.  
Table 1-2

Diameter or smaller section size / mm

≤3

>3~6

>6~12.5

>12.5~25

t/h

1

2

4

8

Nimonic 90 sheet and strip (soft): softened at 1100 ~ 1150 ℃, 1 ~ 10min, cooled in proper medium + 750 ℃ ± 10 ℃, 4 h, air cooling.  
Nimonic 90 sheet and strip (hard state): 700 ~ 725 ℃, 4h, air cooling.  
Cold drawn wire for Nimonic 90 spring: 600 ℃ ± 10 ℃, 16h, air cooling or 650 ℃ ± 10 ℃, 4 h, air cooling.  
Nimonic 90 cold drawn and solution treated spring wire: 1080 ℃ ± 10 ℃, 8h, air cooling + 700-750 ℃, 4h, air cooling.  
Nimonic 90 specification and supply status: cold drawn bar or hexagonal bar with diameter or inscribed circle diameter ≤ 25mm; Cold rolled sheet with thickness ≤ 4mm and cold rolled strip with thickness ≤ 0.8mm; Cold drawn wire for springs with diameter ≤ 8mm. The supply status of cold drawn bar can be divided into: upsetting bar is delivered in cold drawn polished state (when the demander needs to deliver in solid solution state, it shall be indicated in the contract); The bars for machining are delivered in solution and deoxidized condition. Cold rolled sheet and strip (soft state) are delivered after softening treatment, alkali pickling and trimming; Cold rolled sheet and strip (hard state) are delivered after cold rolling and trimming. Spring wire is delivered in cold drawn state or solution treated state after cold drawing.  
Melting and casting process of Nimonic 90

The alloy is melted by one of the following four processes:

  • (1) Induction melting plus electroslag remelting;
  • (2) Vacuum induction melting plus electroslag remelting;
  • (3) Vacuum induction melting plus vacuum arc remelting;
  • (4) Vacuum induction melting.  

Application and special requirements of Nimonic 90

The alloy is used as high temperature spring element, high temperature fastener, combustion chamber clamp ring and stop pin. It is also used as turbine blade, turbine disk and other parts abroad.  
Physical and chemical properties of Nimonic 90  
Thermal properties of Nimonic 90  
The melting temperature range of Nimonic 90 is: melting point 1400 ℃ [1].  
The thermal conductivity of Nimonic 90 is shown in table 2-1.  
Table 2-1 [1]

θ/ ℃

600

700

800

λ/( W/(m·℃))

21.76

23.93

25.57

The linear expansion coefficient of Nimonic 90 is shown in table 2-2.  

Table 2-2 [2]

θ/ ℃

20~100

20~200

20~300

20~400

20~500

20~600

20~700

20~800

20~900

α 1/10-6℃-1

7.71

13.09

13.51

14.04

14.52

15.03

15.58

16.36

17.38

The density of Nimonic 90 was as follows ρ= 8.20g/cm3.  
Electrical properties of Nimonic 90  
The magnetic properties of Nimonic 90: the alloy has no magnetism.  
Chemical properties of Nimonic 90

The alloy has good oxidation resistance and corrosion resistance below 1040 ℃; It is easy to produce intergranular oxidation above 1040 ℃.  
Mechanical properties of Nimonic 90  
Performance specified in technical standard of Nimonic 90
The performance of Nimonic 90 cold drawn bar is shown in table 3-1.  
Table 3-1

Technical standard

θ/ ℃

tensile property

Persistent performance

σ b/MPa

σ P0.2/MPa

δ 5/%

σ/ MPa

t/h

Not less than

WS9 7016-1996

650

820

590

8

870

140

≥30

Note: for the bars supplied in solution state, the mechanical property samples are only subject to aging treatment.  
The properties specified in Nimonic 90 cold rolled sheet and strip (soft state) are shown in table 3-2.  
Table 3-2  

technical standard

θ/ ℃

Thickness of finished product / mm

tensile property

Hardness HV

Persistent performance

σ b/MPa

σ P0.2/MPa

δ 5/%

σ/ MPa

t/h

Not less than

WS9 7087-1996

Room temperature

0.25~0.35

1080

695

15

≥280

>0.35~0.45

1080

695

20

>0.45

1080

695

25

870

All

140

≥30

Note: specimen heat treatment system for endurance test: supply state + 1080 ℃ ± 10 ℃, 8h, air cooling + 700 ℃ ± 10 ℃, 16h, air cooling.  
The properties specified in the technical standard of Nimonic 90 cold rolled sheet and strip (hard state) are shown in table 3-3.  
Table 3-3

Technical standard

θ/ ℃

Tensile property

σ b/MPa

σ P0.2/MPa

WS9 7086-1996

Room temperature

1390~1620

≥1030

See table 3-4 for the performance specified in the technical standard of Nimonic 90 spring wire.
Table 3-4

Technical standard

θ/ ℃

Thickness of finished product / mm

Tensile property

Persistent performance

σ b/MPa

σ P0.2/MPa

δ 5/%

σ/ MPa

t/h

Not less than

WS9 7014-1996

Room temperature

≤1.0

1540

>1.0~5.0

1390

1160

>5.0~8.0

1310

1000

10

870

blank

140

≥30

WS9 7015.1-1996

Room temperature

>0.44~0.99

1080

15

>0.99~8.0

1080

15

870

blank

140

≥30

Note: heat treatment system of billet for endurance test: 1080 ℃ ± 10 ℃, 8h, air cooling + 700 ℃ ± 10 ℃, 16h, air cooling.  
Production inspection data of Nimonic 90  
The statistical treatment results of tensile properties of Nimonic 90 cold drawn bar at 650 ℃ are shown in table 3-5.  
Table 3-5

technical standard

Smelting process

Tensile properties at 650 ℃

σ b/MPa

σ P0.2/MPa

δ 50mm/%

WS9 7016-1996

Vacuum Induction Electroslag

975

670

24

The statistical treatment results of room temperature tensile properties of Nimonic 90 spring wire are shown in table 3-6.  
Table 3-6

technical standard

Smelting process

Wire diameter / mm

Room temperature tensile properties

σ b/MPa

σ P0.2/MPa

δ 50mm/%

WS9 7014-1996

Vacuum induction melting

≤1.0

1800

>1.0~5.0

1515

1260

WS9 7015.1-1996

>0.99~8.0

1180

690

27

Organizational structure of Nimonic 90

The main strengthening phases of the alloy are γ′- Ni3 (al, Ti) precipitates in the grains in the form of square particles with different sizes, which can also be seen on the grain boundaries γ′ Phase. Carbides precipitate in discontinuous chain at grain boundary.  
Technological properties and requirements of Nimonic 90  
Formability of Nimonic 90

The alloy is easy to produce internal crack during forging. Heavy hammer and low temperature chamfering are not allowed. The charging temperature of ingot is not higher than 700 ℃ and the heating temperature is 1150 ℃ ± 10 ℃, the opening forging temperature shall not be lower than 1060 ℃, and the final forging temperature shall not be lower than 950 ℃. The rolling heating temperature is 1160 ℃, and the final rolling temperature is not lower than 950 ℃. After intermediate annealing, the cold drawing should be deformed by 8% – 12%.  
Welding properties of Nimonic 90

The alloy can be welded by inert gas tungsten arc welding and flash butt welding in the solid solution state.  
Heat treatment process of Nimonic 90 parts

The heat treatment process of parts shall be carried out according to the heat treatment system of corresponding material technical standards.  
Surface treatment of Nimonic 90  
The cutting and grinding properties of Nimonic 90 show good machining performance in solution treatment. After aging treatment, the hard tool is used to process slowly according to the specified feed rate.

GH4145

GH4145 alloy is mainly composed of γ”[ The Ni base superalloy aged with Ni3 (al, Ti, Nb)] phase has good corrosion resistance and oxidation resistance below 980 ℃, high strength below 800 ℃, good relaxation resistance below 540 ℃, and good formability and weldability. The alloy is mainly used to make plane spring and coil spring which work under 800 ℃ and require high strength and relaxation resistance. It can also be used to manufacture turbine blades and other parts. The products available are plate, strip, bar, forging, ring, wire and tube[ 1]  
Material grade: GH4145 (GH145)
Similar brands: Inconel X-750 (USA), nicr15fe7tial (Germany), nc15fetnba (France), ncf750 (Japan)  
Technical standards of materials

  • Q / 3b 4088-1994 GH4145 alloy capillary materials  
  • Q / 3b 4098-1995 GH4145 alloy wire  
  • Q / 3b 4198-1993 cold rolled sheet and strip of GH4145 alloy  

chemical composition
Table 1-1

C

Cr

Ni+Co

Al

Ti

Fe

Nb+Ta

Co

Mn

Si

S

Cu

P

≤0.08

14.0~17.0

≥70.0

0.40~1.00

2.25~2.75

5.00~9.00

0.70~1.20

≤1.00

≤1.00

≤0.50

≤0.010

≤0.50

≤0.015

Note: Mn and Si in the table refer to the contents of bars, forgings, annular parts and wires, and the contents of plates, strips and pipes are Mn ≤ 0.35%, Si ≤ 0.35%.  
Heat treatment system
Solution heat treatment system of plate, strip and pipe in supply state 980 ℃ ± 15 ℃, air cooling. For the intermediate heat treatment system of materials and parts, the following processes can be selected for heat treatment.
Annealing: 955 ~ 1010 ℃, water cooling.
Annealing before welding: 980 ℃, 1H.
Stress relief annealing: 900 ℃ for 2 h.
Stress relief annealing: 885 ℃ ± 15 ℃, 24h, air cooling.
Variety specification and supply status
We can supply all kinds of bar, forging, ring, hot rolled plate, cold rolled sheet, strip, pipe and wire.
Plate and strip are generally supplied after hot rolling or cold rolling, annealing or solution, pickling and polishing.
Bars, forgings and rings can be supplied as forged or hot rolled; It can also be supplied by solution treatment after forging; The bar can be polished or polished after solution. When the order requires, it can be placed in the cold drawing state.
Silk can be supplied in solution state; For the wire with nominal diameter or thickness less than 6.35mm, it can be supplied with 50% – 65% cold drawing deformation after solid solution; Wire with nominal diameter or side length greater than 6.35mm shall be supplied with cold drawing deformation of no less than 30% after solution treatment. For wires with nominal diameter or side length ≤ 0.65mm, cold drawing deformation of no less than 15% after solution treatment is required.
Melting and casting process
The alloy is remelted by arc furnace plus vacuum consumable remelting, vacuum induction plus electroslag, electroslag plus vacuum consumable remelting or vacuum induction plus vacuum consumable remelting.
Application Overview and special requirements
The alloy is mainly used for manufacturing corrosion-resistant plane wave spring, circumferential spiral spring, spiral compression spring, spring clamp ring and sealing ring of aeroengine with working temperature below 540 ℃.
Physical and chemical properties
Thermal performance
melting range
1395~1425℃
Thermal conductivity
See table 2-1  

θ/ ℃

fifty

100

300

500

900

λ/( W/(m•C))

14.7

15.9

20.1

25.1

37.3

The linear expansion coefficient of GH4145 (GH145) is shown in table 2-2  

θ/ ℃

20~200

20~300

20~400

20~500

20~600

20~700

20~800

α/ 10-6C-1

13.1

13.5

14.1

14.4

15

15.6

16.2

density
ρ= 8.25g/cm3  
Electrical properties
Resistivity at 50 ℃ ρ= 1.22*10-6 Ω. m  
Metallographic structure
The microstructure of the alloy in standard heat treatment state is determined by γ Matrix, Ti (C, n), Nb (C, n), M23C6 carbide and γ’[ Ni3 (al, Ti, Nb)] phase composition, γ’ The main strengthening phase is about 14.5%.  
Process performance and requirements
1. The forging temperature of the alloy ranges from 1220 ℃ to 950 ℃. The alloy was treated by solid solution after the intensive forming process.  
2. The average grain size of the alloy is closely related to the deformation degree and final forging temperature.  
3. The alloy has good weldability and can be used in all kinds of welding. After welding, aging treatment can obtain the strength of nearly complete heat treatment state.  
4. The heat treatment of parts is carried out in neutral or reducing atmosphere without sulfur to avoid vulcanization.
gif;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVQImWNgYGBgAAAABQABh6FO1AAAAABJRU5ErkJggg== - What are superalloys

GH2132

Material grade
GH2132  
Similar brand of materials
A-286 p.q.a286 unss66286 (USA), zbnct25 (France), GH2132 (GH132) China  
Technical standards of materials

  • GJB 2611-1996 specification for cold drawn superalloy bars for aviation
  • Specification for cold drawn Superalloys for welding (GJB 2612-1996)
  • GJB 3020-1997 specification for superalloy rings for aviation
  • GJB 3165-1998 specification for hot rolled and forged high temperature alloy bars for aircraft load bearing parts
  • GJB 3167-1998 specification for cold drawn Superalloys for cold heading
  • GJB 3317-1998 specification for hot rolled superalloy plates for aviation
  • GJB 3782-1999 specification for high temperature closed forging round cake for aviation
  • GB / T 14992-2005 standard for grades of Superalloys
  • GB / t14993-1994 hot rolled superalloy bars for rotating parts
  • GB / t14994-1994 superalloy cold drawn bars
  • GB / t14995-1994 hot rolled superalloy plates
  • GB / t14996-1994 cold rolled superalloy sheet
  • GB / t14996-1994 cold rolled superalloy sheet
  • GB / t14997-1994 high temperature alloy forged round cake
  • GB / t14998-1994 superalloy blank
  • GB / t15062-1994 general purpose superalloy pipe

Physical and chemical properties
Thermal performance

Melting temperature range :1364~1424℃
   Thermal conductivity See table 2-1  

θ/ ℃

100

200

300

400

500

600

700

800

900

λ/( W/(m.C))

14.2

15.9

17.2

18.8

20.5

22.2

23.9

25.5

27.6

Coefficient of linear expansion  

The coefficient of linear expansion is shown in table 2-2.

θ/ ℃

20~100

20~200

20~300

20~400

20~500

20~600

20~700

20~800

20~900

a/10-6℃C-1

15.37

16.09

16.31

16.84

17.58

18.06

18.74

19.62

20.45

The linear expansion coefficient of high quality alloy is shown in table 2-3

θ/ ℃

20~100

20~200

20~300

20~400

20~500

20~600

20~700

20~800

20~900

a/10-6℃C-1

15.7

16

16.5

16.8

17.3

17.5

17.9

19.1

19.7

Density

  • ρ= 7.93g/cm3  

Electrical properties
The resistivity is shown in table 2-4.  

θ/ ℃

20

100

200

300

400

ρ/( 10-6 Ω. M)

0.914

0.985

1.018

1.074

1.111

Table 2-4 continued


θ/ ℃

500

600

700

800

900

ρ/( 10-6 Ω. M)

1.135

1

1.018

1.074

1.119

Magnetic properties
Chemical properties
Oxidation resistance

The oxidation rate of the alloy after 100-300h test in air medium is shown in table 2-5.

θ/ ℃

Oxidation rate / (g / (M2 · h))

Oxidation rate / (g / (M2 · h))

Oxidation rate / (g / (M2 · h))

θ/ ℃

Oxidation rate / (g / (M2 · h))

Oxidation rate / (g / (M2 · h))

Oxidation rate / (g / (M2 · h))

100h

200h

300h

100h

200h

300h

650

0.00417

0.00276

0.00234

850

0.11630

0.12386

0.09672

750

0.03250

0.07216

0.08322

Metallographic structure
The alloy is in the standard heat treatment state, and γ The Ni3 (Ti, Al) type with spherical shape uniformly dispersed on the matrix γ’ There may be a small amount of m3b2 near the grain boundary η Phase and L phase  
Process performance and requirements
1. The results show that the alloy has good malleability. The forging heating temperature is 1140 ℃ and the final forging temperature is 900 ℃.
2. The average grain size of the alloy is closely related to the deformation degree and final forging temperature.
3. The alloy has satisfactory welding properties. The alloy was welded in solution state and aged after welding.

GH1140

GH1140 is a solution strengthened Fe Ni base superalloy. In addition to a large amount of chromium, a small amount of tungsten, molybdenum, aluminum and titanium are used to strengthen the solid solution. The alloy has medium thermal strength, high plasticity, good thermal fatigue, microstructure stability and welding process properties. It is suitable for manufacturing plate structure parts and other high temperature parts of aeroengine and gas turbine combustor with working temperature below 850 ℃. It can supply various deformed products such as plate, bar, tube, wire, strip and forging.
Material grade
GH1140(GH140,CR-2)  
Technical standards of materials

  • GJB 1952-1994 specification for cold rolled high temperature alloy sheet for aviation
  • GJB 2297-1995 specification for cold drawn (rolled) seamless tubes of superalloy for aviation
  • GJB 2612-1996 specification for cold drawn Superalloys for aviation
  • GJB 3020-1997 specification for superalloy rings for aviation
  • GJB 3317-1998 specification for hot rolled superalloy plates for aviation  
  • GJB 3318-1998 specification for cold rolled high temperature alloy strip for aviation
  • GJB 3165-1998 specification for hot rolled and forged high temperature alloy bars for aircraft load bearing parts
  • GJB 3167-1998 specification for cold drawn Superalloys for cold heading
  • GB / T 15062-1994 superalloy tubes for general use

Heat treatment system
Solution treatment: hot rolled plate, cold rolled sheet and strip 1050 ~ 1090 ℃, air cooling; The temperature of wire and pipe is 1050-1080 ℃, air cooling or water cooling; Bar and ring billet 1080 ° C ± 10 ℃, air cooling.  
Variety specification and supply status
We can supply all kinds of hot rolled plate, cold rolled plate, strip, bar, wire, tube, forging and ring. Plate, pipe, wire and strip are supplied after solution treatment and acid pickling. Bars and rings are supplied in hot rolled or forged condition. Forgings are supplied in forged state or after solution treatment.  
Melting and casting process
Electric arc furnace melting or electric arc furnace + electroslag remelting.  
Application Overview and special requirements
It has been used to manufacture combustion chamber flame tube, afterburner diffuser, rectifying support plate, stabilizer, fuel ring, afterburner adjustable nozzle shell, pipe joint, bushing and aircraft tail cover skin and other parts, and put into mass production. In the temperature range of 550-800 ℃, there is a sliGHt hardening phenomenon after long-term use, which makes the room temperature plasticity decrease. The high temperature oxidation resistance above 1000 ℃ is sliGHtly worse than that of nickel base alloys for similar applications.  
Physical and chemical properties
Thermal performance
Density

  • ρ= 8.09g/cm3  

Electrical properties
Room-temperature resistivity ρ= 1.07*10-6 Ω. m  
Magnetic properties
The alloy has no magnetism.  
Chemical properties
  Oxidation resistance

See table 2-1 for oxidation rate of alloy in air medium for 100h.  

θ/ ℃

700

800

900

1000

1100

Oxidation rate / (g / (m2. H))

0.014

0.028

0.139

0.270

0.523

The oxidation along grain boundary occurs when the alloy works for a long time above 700 ℃. The oxidation depth of grain boundary was observed at 700 ℃ ~ 1200 ℃ for 100 h. The oxidation depth of grain boundary was observed at 700-900 ℃ for 1000 H.
When the flame tube made of this alloy works at higher than 900 ℃ for a long time, it may produce oxidation and spalling; The rate of oxidation spalling was 0.016 mm / 100h. See table 2-2 for oxidation spalling depth of middle section of flame tube after long-term operation.

Alloy

Oxidation peeling depth / mm

Oxidation peeling depth / mm

200h

800h

GH1140

0.032

0.127

GH3039

0.116

65, 66-4, W-2 and w69-1 enamel coatings can be used for long-term protection at high temperature, and solid Aluminizing and vacuum spray coating can also be used. See table 2-3 for comparison of oxidation resistance between alloy matrix and coating.

Material grade

100h oxidation rate / (g / (m2. H))

100h oxidation rate / (g / (m2. H))

100 h intergranular oxidation depth/ μ m

100 h intergranular oxidation depth/ μ m

900℃

1000℃

900℃

1000℃


GH1140

0.062

0.236

10~20

26~30

GH1140 + 65 coating

0.055

0.081

11~15

30

GH1140 + 66-4 coating

0.047

0.071

11~15

30

Material grade

100h oxidation rate / (g / (m2. H))

100h oxidation rate / (g / (m2. H))

100 h intergranular oxidation depth/ μ m

100 h intergranular oxidation depth/ μ m

900℃

1000℃

900℃

1000℃

GH1140 + W2 coating

0.076

GH1140 + solid aluminizing

0.030

GH1140 + vacuum spray aluminum plating

0.027

Corrosion resistance

  • Domestic aviation kerosene with or without CS2 additive has no corrosive effect on GH1140 alloy, but for nickel base alloy, additive is necessary to prevent corrosion. If foreign aviation kerosene is used, it is sometimes found that the corrosion is serious.  
  • Process performance and requirements Thermoforming process During forging, furnace temperature ≤ 700 ℃, heating temperature 1160 ℃ ± The terminal temperature shall not be lower than 900 ℃.
  • Slab hot rolling heating temperature 1160 ℃ ± The rolling temperature is 1180 ~ 950 ℃ at 20 ℃, and the temperature is controlled within 950 ~ 1000 ℃ when entering the last pass.
  • The results show that the heating temperature of hot rolling plate is 1120 ℃ and that of hot rolling temperature is 1120 ~ 850 ℃, and the total deformation is more than 50%.
  • The rolling reduction of cold rolled sheet is 30% ~ 40%, and the flatness deformation of finished plate shall not be more than 3%.  

Cold formability
The sheet has good plasticity and the forming process is carried out at room temperature. When parts are manufactured by multiple forming process, intermediate and heat treatment is carried out after each cold forming. Before molding, the surface of parts was coated with nitrocellulose varnish.

Preparation technology

1. Foundry metallurgy process
All kinds of advanced casting manufacturing technology and processing equipment are constantly developed and improved, such as thermal control solidification, fine grain technology, laser forming repair technology, wear-resistant casting technology, etc. the original technical level is constantly improved, so as to improve the quality consistency and reliability of various superalloy casting products.
High temperature alloys without or with little aluminum and titanium are usually smelted in electric arc furnace or non vacuum induction furnace. If the high temperature alloy containing aluminum and titanium is melted in the atmosphere, the element burning loss is not easy to control, and the gas and inclusions enter more, so vacuum smelting should be adopted. In order to further reduce the content of inclusions, improve the distribution of inclusions and the crystal structure of ingot, the duplex process of smelting and secondary remelting can be used. The main means of smelting are electric arc furnace, vacuum induction furnace and non vacuum induction furnace; The main means of remelting are vacuum consumable furnace and electroslag furnace.
Solution strengthened alloy and alloy ingot with low Al and Ti content (the total amount of Al and Ti is less than 4.5%) can be forged; The alloy with high content of Al and Ti is usually extruded or rolled, and then hot rolled. Some products need further cold rolling or cold drawing. The alloy ingot or cake with larger diameter should be forged by hydraulic press or rapid forging hydraulic press.
2. Crystallization metallurgy process
In order to reduce or eliminate the grain boundary perpendicular to the stress axis and porosity in cast alloys, directional crystallization process has been developed in recent years. The process is to make the grains grow along one direction of crystallization during the solidification of the alloy, so as to obtain parallel columnar grains without transverse grain boundaries. The primary process conditions for directional crystallization are to establish and maintain a large enough axial temperature gradient and good axial heat dissipation conditions between liquidus and solidus. In addition, in order to eliminate all grain boundaries, it is necessary to study the manufacturing process of single crystal blade.
3. Powder metallurgy process
Powder metallurgy process is mainly used to produce precipitation strengthened and oxide dispersion strengthened superalloys. This process can make the cast superalloy which can not be deformed obtain plasticity or even superplasticity.
4. Strength improvement process
(1) solid solution strengthening
The addition of elements (Cr, W, Mo, etc.) with different atomic sizes to the base metal will cause the lattice distortion of the base metal. The addition of elements (such as CO) which can reduce the stacking fault energy of the alloy matrix and elements (such as W, Mo, etc.) which can slow down the diffusion rate of the base metal will strengthen the base metal.
(2) precipitation strengthening
The second phase was precipitated from supersaturated solid solution by aging treatment( γ’、γ”、 Carbide, etc.) to strengthen the alloy. γ‘ The lattice constant is close to that of the matrix and is coherent with the crystal γ The results show that the phase can precipitate uniformly in the form of fine particles in the matrix, which hinders the movement of dislocations and produces significant strengthening effect. γ’ The phase is a3b type intermetallic compound, a represents nickel and cobalt, B represents aluminum, titanium, niobium, tantalum, vanadium and tungsten, while chromium, molybdenum and iron can be both a and B. Typical corrosion resistance in nickel based alloys γ‘ The phase is Ni3 (al, Ti).
γ’ Strengthening effect of phase can be enhanced by the following ways:

  • ① Increase γ‘ The number of phases;
  • ② Make γ’ In order to obtain the strengthening effect of coherent distortion, there is an appropriate mismatch between the phase and the matrix;
  • ③ The addition of niobium, tantalum and other elements increased the temperature γ’ In order to improve its ability to resist dislocation cutting, the antiphase domain boundary energy of the phase is increased;
  • ④ Adding cobalt, tungsten, molybdenum and other elements to improve γ‘ The strength of the phase. γ” The phase is body centered tetragonal structure and its composition is ni3nb. because γ” The mismatch between the phase and the matrix is large, which can cause a large degree of coherent distortion and make the alloy obtain a high yield strength. However, when the temperature is higher than 700 ℃, the strengthening effect will decrease obviously. Cobalt based superalloys generally do not contain γ It is strengthened by carbides.

Material properties

In the high temperature environment, all kinds of degradation rates of materials are accelerated. In the process of using, it is easy to have instability of structure, deformation and crack growth under the action of temperature and stress, and oxidation corrosion of material surface.
1. High temperature and corrosion resistance
The high temperature resistance and corrosion resistance of Superalloy mainly depend on its chemical composition and microstructure. Taking GH4169 nickel base wrought superalloy as an example, it can be seen that the content of niobium in GH4169 alloy is high, and the degree of niobium segregation in the alloy is directly related to the metallurgical process. The matrix of GH4169 is Ni GR solid solution, with more than 50% Ni content, it can withstand high temperature of about 1000 ℃, similar to American Inconel 718 γ  Matrix phase δ  Phase, carbide and strengthening phase γ’ and γ″ Phase composition. The chemical elements and matrix structure of GH4169 alloy show its strong mechanical properties. Its yield strength and tensile strength are several times better than those of 45 steel, and its plasticity is also better than that of 45 steel. Stable lattice structure and a large number of strengthening factors construct its excellent mechanical properties.
2. High processing difficulty
Due to the complex and harsh working environment of superalloy, the machined surface integrity plays a very important role in its performance. However, superalloy is a typical difficult to machine material, its micro hardness is high, the work hardening degree is serious, and it has high shear stress resistance and low thermal conductivity, high cutting force and cutting temperature in the cutting area. In the process of machining, the problems of low surface quality and serious tool damage often appear. Under general cutting conditions, the surface of Superalloy will produce too large hardening layer, residual stress, white layer, black layer and grain deformation layer.

Source: China Superalloy Flanges Manufcturer – Yaang Pipe Industry (www.steeljrv.com)

(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)

If you want to have more information about the article or you want to share your opinion with us, contact us at sales@steeljrv.com

Please notice that you might be interested in the other technical articles we’ve published:

Related News

  • * 暂无相关文章
العربيةБългарски简体中文繁體中文DanskNederlandsEnglishFrançaisDeutschBahasa IndonesiaItaliano日本語한국어LatinPortuguêsРусскийEspañolதமிழ்ไทยTürkçe