Preparation method of high-uniformity GH4169 high-temperature alloy bar

Abstract

The invention provides a preparation method of a high-uniformity GH4169 high-temperature alloy bar. According to the preparation method, the high-uniformity GH4169 alloy bar is prepared by adopting a high-uniformity annealing and free forging technology; the method comprises the following steps: firstly, carrying out 2-3 heating number axial upsetting and drawing cogging forging and 2-3 heating number radial upsetting and drawing forging on a GH4169 alloy, and then carrying out high-uniformity annealing heat treatment; after heat treatment, the blank is subjected to 2-3 heating number radial upsetting and drawing forging, and then secondary high-uniformity annealing heat treatment is carried out; after the secondary heat treatment, the blank is subjected to twice radial forging of 2-3 heating numbers, and air cooling is carried out after the forging is completed; and finally, the blank is subjected to 2-3 heating number drawing forming after being subjected to heat preservation at the temperature of 980-1010 DEG C, and air cooling is conducted after forging is completed. Compared with the prior art, the structure uniformity of the large bar billet is further improved, the mechanical property of the alloy is improved, the performance consistency in different directions at room temperature / high temperature is improved, and the complex force bearing condition of the high-temperature alloy material for the aero-engine can be met; the method has the advantages of simple process, low production cost and high material utilization rate.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal material preparation, and relates to a preparation method of high-uniform GH4169 high-temperature alloy rod, that is, a process flow and process control method for preparing the GH4169 alloy rod by adopting fast forging technology, so that the organization and mechanical properties of the rod in different directions are uniform. The method helps to improve the service life of an aero-engine. BACKGROUND

[0002] The GH4169 alloy for an aircraft has excellent room temperature and high-temperature performance, can bear the high centrifugal force of an aero-engine at a high speed, has good corrosion resistance and welding performance, and accounts for more than 40% of the use of deformation high-temperature alloy materials for advanced aero-engines.

[0003] In recent years, with the rapid development of long-life aero-engines, higher requirements are put forward for the performance stability of high-temperature alloy for an engine. However, due to the microsegregation, inclusion distribution and deformation streamline of the traditional high-temperature alloy material, the mechanical properties in different detection directions are quite different. Previous researches mainly aimed at improving the strength of the material, and less considered the consistency of the mechanical properties of the alloy in different directions. However, the high-temperature alloy parts for an aero-engine are numerous, and the bearing conditions are complex. If the performance in a certain direction is poor, it may cause the service life of the aero-engine to be difficult to meet the use requirements. Therefore, it is urgent to develop a preparation process of high-temperature alloy for an aero-engine with balanced bearing performance in all directions.

[0004] At present, the method of improving the uniformity of the organization is mostly used to improve the strength of the GH4169 high-temperature alloy rod at home and abroad. According to the domestic patent technology “a GH4169 high-temperature alloy free forging rod blank and a preparation method thereof” (CN201910701846.0), the GH4169 high-temperature alloy ingot is smelted by the three-in-one smelting process of “vacuum induction melting + electroslag remelting + vacuum consumable remelting”, and after 1-time high-temperature uniform treatment, upsetting and opening blanking and conventional continuous re-furnace drawing forging are performed to obtain the GH4169 high-temperature alloy free forging rod blank with a grain size of 8-9 levels, and the grain size level difference from the edge to the center is controlled within 1 level, so that the uniformity of the large rod blank is improved. However, the problem of poor consistency of the performance in different bearing directions still exists, and it is difficult to meet the requirements of the long-life aero-engine GH4169 alloy.

[0005] The application fully considers the development trend of domestic aero-engines, and proposes a preparation method of high-uniform GH4169 high-temperature alloy rod. The rod has excellent mechanical properties, and the performance difference in different bearing directions is small at room temperature and high temperature, so that the complex bearing conditions of the high-temperature alloy material for an aero-engine can be met. SUMMARY

[0006] A preparation method of high-uniform GH4169 high-temperature alloy rod, comprising the following steps:

[0007] Step (1): 2-3 fire axial upsetting and drawing breakdown forging of the GH4169 high-temperature alloy ingot after high-temperature homogenization heat treatment is performed on the 80MN fast forging machine, and the breakdown forging is continuous recycling, and the deformation amount of each fire is 30%-50%;

[0008] Step (2): then, 2-3 fire radial upsetting and drawing forging of the blank is performed on the 80MN fast forging machine, and the forging is continuous recycling, and the deformation amount of each fire is 30%-50%;

[0009] Step (3): the forged blank is subjected to high-uniform annealing heat treatment in a natural gas furnace;

[0010] Step (4): then, 2-3 fire radial upsetting and drawing forging of the blank is performed on the 80MN fast forging machine, and the forging is continuous recycling, and the deformation amount of each fire is 30%-50%;

[0011] Step (5): the forged blank is subjected to secondary high-uniform annealing heat treatment in a natural gas furnace;

[0012] Step (6): 2-3 fire radial upsetting and drawing forging of the blank after the secondary annealing heat treatment is performed on the 80MN fast forging machine, and the forging is continuous recycling, and the deformation amount of each fire is 30%-50%;

[0013] Step (7): then, 2-3 fire radial upsetting and drawing forging of the blank is performed on the 80MN fast forging machine, and the forging is continuous recycling, and the deformation amount of each fire is 30%-50%;

[0014] Step (8): 2-3 fire axial lengthening drawing forging of the blank is performed on the 80MN fast forging machine, and the forging is continuous recycling, and the deformation amount of each fire is 30%-50%.

[0015] As preferred, the heat treatment method of steps (3) and (5) is:

[0016] After the furnace temperature is raised to 1060-1100℃, the material is put into the furnace, the holding time is 2-3h, then the temperature is rapidly raised to 1200-1210℃, the holding time is 50-60h, and then air cooling is performed.

[0017] As preferred, the heating and cooling of steps (1), (2), (4), (6), (7) and (8) are respectively:

[0018] The step (1) is as follows: the cold material is charged into the furnace and heated to 500°C with a thermal insulation coefficient of 0.6 min / mm, then the temperature is raised to 1120°C to 1140°C at a heating rate of 3°C to 5°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed;

[0019] Step (2): heating to 1120° C. to 1140° C., with a thermal insulation coefficient of 0.8 min / mm, a thermal insulation coefficient of 0.3 min / mm for hot material returning to the furnace, and air cooling after forging;

[0020] The step (4) is as follows: the cold material is charged into the furnace and heated to 700°C with a thermal insulation coefficient of 0.6 min / mm, and then the temperature is increased to 1120°C to 1140°C at a heating rate of 5°C to 10°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed;

[0021] Step (6): the cold material is charged into the furnace and heated to 500°C with a thermal insulation coefficient of 0.6 min / mm, then the temperature is raised to 1120°C to 1140°C at a heating rate of 3°C to 5°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed;

[0022] Step (7): the cold material is charged into the furnace and heated to 700°C with a thermal insulation coefficient of 0.6 min / mm, then heated to 1020°C to 1040°C at a heating rate of 5°C to 10°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed;

[0023] The step (8) is to heat the material to 1020° C. to 1040° C., with a thermal insulation coefficient of 0.8 min / mm, a thermal insulation coefficient of 0.3 min / mm for the hot material to be returned to the furnace, and air-cool the material after forging.

[0024] Preferably, the difference in room temperature tensile strength of the rod in the axial, radial and chord directions is ≤20 MPa, and the difference in elongation is ≤5%; the difference in high temperature tensile strength at 650°C is ≤20 MPa, and the difference in elongation is ≤5%.

[0025] Compared with the prior art, the present invention has the following technical effects:

[0026] (1) Using upsetting and reversing upsetting and blanking technology, adding two high-temperature uniform heat treatments, improving the consistency of the billet composition and uniform distribution of inclusions;

[0027] (2) By reasonable temperature and deformation matching, the grain size of the GH4169 high-temperature alloy bar is controlled at the level of 6-7 grade grain size, the mechanical property difference of the bar in different force directions is small, and the mechanical property is excellent under room temperature and high temperature conditions;

[0028] (3) The requirements of the GH4169 high-temperature alloy bar for the long life cycle aero-engine are met, and the reliability and long life of the key components of the engine are ensured. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 Microstructure morphology of the center position of the bar in Example 1

[0030] The specific content of the present application is further explained and described in detail in combination with the following examples. DETAILED DESCRIPTION

[0031] In the embodiment of the present application, the room temperature tensile test is carried out at room temperature according to the national standard GB / T 228.1.

[0032] In the embodiment of the present application, the high temperature tensile test is carried out after 20 min of heat preservation at 650 DEG C according to the national standard GB / T 228.2.

[0033] Example 1

[0034] The GH4169 ingot after high-temperature homogenization heat treatment has a diameter of 495 mm.

[0035] The cold charge of the ingot is loaded into the furnace, heated to 500 DEG C and heat preserved, then heated to 1120 DEG C at a heating rate of 3 DEG C / min and heat preserved, and then opened in the 80MN fast forging machine, and the opening forging is completed for 3 heats, and the deformation settings are as follows: Φ495x1000→[axial upsetting]Φ600x680(30%)→[axial drawing]□445x970(30%)→[axial upsetting]□630x485(50%), and then air cooling is performed.

[0036] The blank is radially upset and drawn after heat preservation at 1120 DEG C in the 80MN fast forging machine, and the deformation settings are as follows: □630x485→[radial drawing]480(radial 2)x430(axial)x930(radial 1)(48%)→[radial upsetting]575(radial 2)x515(axial)x650(radial 1)(30%)→[radial drawing]385(radial 2)x385(axial)x1300(radial 1)(50%), and then air cooling is performed.

[0037] Ingot high homogenization annealing heat treatment: the furnace temperature is heated to 1060 DEG C, the material is loaded into the furnace, the heat preservation time is 2h, then the temperature is rapidly increased to 1200 DEG C, the heat preservation time is 60h, and then air cooling is performed.

[0038] The homogenized billet was forged in an 80MN forging machine, heated to 700°C, then heated to 1120°C at a heating rate of 5°C / min, and forged for 2 heats with the following deformation settings: 385 (radial 2) x 385 (axial) x 1300 (radial 1)→[radial upsetting]□545 x 650 (radial 1) (50%)→[radial drawing] 540 (radial 1) x 455 (axial) x 785 (radial 2) (30%), and air-cooled after completion.

[0039] Ingot high homogenization heat treatment: the furnace temperature was raised to 1060°C, the material was put into the furnace, the holding time was 2h, then rapidly heated to 1210°C, the holding time was 60h, and then air-cooled.

[0040] Heated to 500°C, then heated to 1120°C at a heating rate of 3°C / min, and forged in an 80MN forging machine for 2 heats with the following deformation settings: 540 (radial 1) x 455 (axial) x 785 (radial 2)→[radial upsetting]□545 x 650 (radial 1) (30%)→[radial drawing]□455 x 930 (radial 1) (30%), and air-cooled after completion.

[0041] Heated to 700°C, then heated to 1020°C at a heating rate of 5°C / min, and forged in an 80MN forging machine for 3 heats with the following deformation settings: □455 x 930 (radial 1)→[radial upsetting]□640 x 470 (radial 1) (50%)→[radial drawing]□455 x 930 (radial 1) (50%)→[radial upsetting]□640 x 470 (radial 1) (50%), and air-cooled after completion.

[0042] The billet was forged in an 80MN forging machine for 2 heats with the following deformation settings: □640 x 470 (radial 1)→[axial drawing] 535 (radial 1) x 395 (radial) x 915 (axial) (30%)→[axial drawing] Φ430 x 1325 (axial) (30%)→[axial drawing] Φ360 x 1890 (axial) (30%), and air-cooled after completion.

[0043] The grain size of the finished rod was rated as 6 levels according to GB / T 6394, and the specific performance parameters are shown in Table 1.

[0044] Example 2

[0045] The GH4169 ingot after high-temperature homogenization heat treatment had a diameter of 495mm.

[0046] The ingot is heated to 500°C and kept for 2 hours, then heated to 1140°C at a rate of 4°C / min, and kept for 2 hours. The ingot is forged on an 80MN fast forging machine, and the deformation setting is as follows: Φ495x600→ [axial drawing] 310x1200 (50%)→ [axial upsetting] 440x600 (50%), and then air-cooled.

[0047] The ingot is heated to 500°C and kept for 2 hours, then heated to 1140°C at a rate of 4°C / min, and kept for 2 hours. The ingot is forged on an 80MN fast forging machine, and the deformation setting is as follows: Φ495x600→ [axial drawing] 310x1200 (50%)→ [axial upsetting] 440x600 (50%), and then air-cooled.

[0048] The ingot is heated to 500°C and kept for 2 hours, then heated to 1140°C at a rate of 4°C / min, and kept for 2 hours. The ingot is forged on an 80MN fast forging machine, and the deformation setting is as follows: Φ495x600→ [axial drawing] 310x1200 (50%)→ [axial upsetting] 440x600 (50%), and then air-cooled.

[0049] The ingot is heated to 500°C and kept for 2 hours, then heated to 1140°C at a rate of 4°C / min, and kept for 2 hours. The ingot is forged on an 80MN fast forging machine, and the deformation setting is as follows: Φ495x600→ [axial drawing] 310x1200 (50%)→ [axial upsetting] 440x600 (50%), and then air-cooled.

[0050] The ingot is heated to 500°C and kept for 2 hours, then heated to 1140°C at a rate of 4°C / min, and kept for 2 hours. The ingot is forged on an 80MN fast forging machine, and the deformation setting is as follows: Φ495x600→ [axial drawing] 310x1200 (50%)→ [axial upsetting] 440x600 (50%), and then air-cooled.

[0051] The ingot is heated to 500°C and kept for 2 hours, then heated to 1140°C at a rate of 4°C / min, and kept for 2 hours. The ingot is forged on an 80MN fast forging machine, and the deformation setting is as follows: Φ495x600→ [axial drawing] 310x1200 (50%)→ [axial upsetting] 440x600 (50%), and then air-cooled.

[0052] Heating to 700℃, then heating to 1040℃ at a rate of 8℃ / min, holding, then radial upsetting and drawing on an 80MN fast forging machine, a total of 2 heats, with the deformation settings as follows: □305x1230 (radial 1)→[radial upsetting] □430x615 (radial 1) (50%)→[radial drawing] □305x1230 (radial 1) (50%), and then air cooling.

[0053] The blank is heated to 1040℃, then axial upsetting and drawing on an 80MN fast forging machine, a total of 2 heats, with the deformation settings as follows: □305x1230 (radial 1)→[axial drawing] 215 (radial 1) x870 (radial 2) x610 (axial) (50%)→[axial drawing] 215 (radial 1) x435 (radial 2) x1220 (axial) (50%)→[axial drawing] Φ290x1750 (axial) (30%), and then air cooling.

[0054] The grain size of the finished rod is rated as 6 levels according to GB / T 6394, and the specific performance parameters are shown in Table 1.

[0055] Example 3

[0056] The GH4169 cast ingot after high-temperature homogenization heat treatment has a diameter of 495mm.

[0057] The cold charge of the cast ingot is loaded into the furnace, heated to 500℃, then heated to 1130℃ at a rate of 5℃ / min, holding, then cogging on an 80MN fast forging machine, with the cogging forging being a total of 2 heats, with the deformation settings as follows: Φ495x1000→[axial upsetting] Φ640x600 (40%)→[axial drawing] □440x1000 (40%), and then air cooling.

[0058] The blank is heated to 1130℃, then radial upsetting and drawing on an 80MN fast forging machine, a total of 3 heats, with the deformation settings as follows: □440x1000→[radial drawing] 340 (radial 2) x775 (axial) x735 (radial 1) (40%)→[radial drawing] □395x1225 (radial 1) (40%)→[radial upsetting] □510x740 (radial 1) (40%), and then air cooling.

[0059] Cast ingot high uniform annealing heat treatment: the furnace temperature is raised to 1080℃, the material is put into the furnace, the holding time is 2.5h, then rapidly heated to 1205℃, the holding time is 55h, and then air cooling.

[0060] The homogenization heat treatment of the blank was followed by heating to 700°C, holding, then heating to 1130°C at a rate of 10°C / min, holding, and forging on an 80MN forging machine in 2 heats with the following deformation settings: 510x740 (radial 1)→[radial drawing] 575 (radial 1) x 395 (axial) x 850 (radial 2) (40%)→[radial upsetting] 510x740 (radial 1) (40%)→[radial drawing] 575 (radial 1) x 395 (axial) x 850 (radial 2) (40%), and air cooling after completion.

[0061] The ingot high homogenization heat treatment was as follows: the furnace temperature was raised to 1080°C, the material was put into the furnace, the holding time was 2.5h, then the temperature was rapidly raised to 1205°C, the holding time was 55h, and then air cooling.

[0062] Heating to 500°C, holding, then heating to 1130°C at a rate of 5°C / min, holding, and forging on an 80MN forging machine in 2 heats with the following deformation settings: 575 (radial 1) x 395 (axial) x 850 (radial 2)→[radial drawing] 305 (radial 2) x 660 (axial) x 960 (radial 1) (40%)→[radial upsetting] 575 (radial 1) x 395 (axial) x 850 (radial 2) (40%)→[radial drawing] 445 x 960 (radial 1) (40%), and air cooling after completion.

[0063] Heating to 700°C, holding, then heating to 1030°C at a rate of 10°C / min, holding, and radial upsetting and drawing on an 80MN forging machine in 2 heats with the following deformation settings: 445 x 960 (radial 1)→[radial upsetting] 575 x 560 (radial 1) (40%)→[radial drawing] 445 x 960 (radial 1) (50%)→[radial upsetting] 575 x 560 (radial 1) (40%), and air cooling after completion.

[0064] The blank was axially upset and drawn on an 80MN forging machine after holding at 1030°C in 2 heats with the following deformation settings: 575 x 560 (radial 1)→[axial drawing] 440 x 955 (axial) (40%)→[axial drawing] 340 x 1590 (axial) (40%)→[axial drawing] 300 x 2660 (axial) (40%), and air cooling after completion.

[0065] The grain size of the finished rod was rated as 7 levels according to GB / T 6394, and the specific performance parameters are shown in Table 1.

[0066] Table 1

[0067]

Claims

1. A method for preparing a high-uniform GH4169 high-temperature alloy bar, characterized by: The following steps are involved: Step (1): subjecting the GH4169 high-temperature alloy ingot that has undergone high-temperature homogenization heat treatment to 2-3 fires of axial upsetting and blanking forging in an 80MN fast forging machine, wherein the blanking forging is continuous remelting, and the deformation amount of each fire is 30% to 50%; Step (2): The blank is then subjected to 2-3 rounds of radial upsetting forging on an 80MN fast forging machine, with continuous reheating and a deformation of 30% to 50% per round; Step (3): the forged billet is subjected to high uniformity annealing heat treatment in a natural gas furnace; Step (4): The blank is then subjected to 2-3 rounds of radial upsetting forging on an 80MN fast forging machine, with continuous reheating and a deformation of 30% to 50% per round; Step (5): the forged billet is subjected to secondary high uniformity annealing heat treatment in a natural gas furnace; Step (6): the blank after secondary annealing heat treatment is subjected to 2-3 rounds of radial upsetting forging in an 80MN fast forging machine, the forging is continuous remelting, and the deformation amount of each fire is 30% to 50%; Step (7): The blank is then subjected to 2-3 rounds of radial upsetting forging on an 80MN fast forging machine, with continuous reheating and a deformation of 30% to 50% per round; Step (8): The blank is subjected to 2-3 fire axial drawing forging on an 80MN fast forging machine. The forging is continuous remelting, and the deformation amount of each fire is 30% to 50%.

2. The method for preparing a high-uniform GH4169 high-temperature alloy bar according to claim 1, characterized in that: The heat treatment method of step (3) and step (5) is: After the furnace temperature rises to 1060℃~1100℃, the materials are put into the furnace and kept warm for 2h~3h. Then the temperature is quickly raised to 1200℃~1210℃, kept warm for 50h~60h, and then air-cooled.

3. The method for preparing a high-uniform GH4169 high-temperature alloy bar according to claim 1, characterized in that: The heating and cooling of step (1), step (2), step (4), step (6), step (7) and step (8) are respectively: The step (1) is as follows: the cold material is charged into the furnace and heated to 500°C with a thermal insulation coefficient of 0.6 min / mm, then the temperature is raised to 1120°C to 1140°C at a heating rate of 3°C to 5°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed; Step (2): heating to 1120° C. to 1140° C., with a thermal insulation coefficient of 0.8 min / mm, a thermal insulation coefficient of 0.3 min / mm for hot material returning to the furnace, and air cooling after forging; The step (4) is as follows: the cold material is charged into the furnace and heated to 700°C with a thermal insulation coefficient of 0.6 min / mm, and then the temperature is increased to 1120°C to 1140°C at a heating rate of 5°C to 10°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed; Step (6): the cold material is charged into the furnace and heated to 500°C with a thermal insulation coefficient of 0.6 min / mm, then the temperature is raised to 1120°C to 1140°C at a heating rate of 3°C to 5°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed; Step (7): the cold material is charged into the furnace and heated to 700°C with a thermal insulation coefficient of 0.6 min / mm, then heated to 1020°C to 1040°C at a heating rate of 5°C to 10°C / min with a thermal insulation coefficient of 0.6 min / mm, the hot material is returned to the furnace with a thermal insulation coefficient of 0.3 min / mm, and air-cooled after forging is completed; The step (8) is to heat the material to 1020° C. to 1040° C., with a thermal insulation coefficient of 0.8 min / mm, a thermal insulation coefficient of 0.3 min / mm for the hot material to be returned to the furnace, and air-cool the material after forging.

4. The method for preparing a high-uniform GH4169 high-temperature alloy bar according to claim 1, characterized in that: The difference in tensile strength in the axial, radial and chord directions at room temperature of the bar is ≤20MPa, and the difference in elongation is ≤5%; the difference in tensile strength in the high temperature of 650℃ is ≤20MPa, and the difference in elongation is ≤5%.

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