A method for producing a high-temperature alloy bar

Abstract

A preparation method of high-temperature alloy rod, which adopts a transverse elongation forging method, and the used raw material ingot is subjected to high-temperature homogenization, the prepared GH4698 high-temperature alloy rod has a specification of Φ200mm-300mm, the macrostructure of the rod is uniform, the grain size reaches 3-4 levels, the carbide distribution is more uniform, meanwhile, the transverse performance of the rod after heat treatment is improved to a certain extent, and the transverse and longitudinal performances can both meet the corresponding standard requirements, the forging method improves the uniformity of the rod structure by optimizing the deformation mode, and reduces the anisotropy of the rod, and successfully breaks through the performance requirements and the uniformity requirements of the GH4698 high-temperature alloy rod.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of non-ferrous metal processing, and particularly relates to a preparation method of high-temperature alloy bar. BACKGROUND

[0002] GH4698 alloy is a Ni-Cr-based precipitation hardening type deformed high-temperature alloy, and the service temperature is 750 DEG C to 800 DEG C. The alloy is developed on the basis of GH4033 alloy, and compared with the GH4033 alloy, the content of aluminum and titanium is increased, the content of niobium and molybdenum is added, and the content of chromium is reduced. The alloy has high creep strength and tensile strength, good plasticity and comprehensive performance, and long-term use organizational stability in the range of 550 DEG C to 800 DEG C. The alloy is suitable for manufacturing long-life heavy-load parts such as engine turbine disc and compressor disc. The alloy has been used for manufacturing large-size turbine disc and other parts of marine gas turbine.

[0003] Since the GH4698 alloy has many elements, the content of Al, Ti and Nb elements is as high as 5.70% to 6.75%, and the content of C is about 0.045%. Therefore, the deformation resistance of the alloy is large, and the plastic forming is not easy to process. Secondly, the alloy has poor processing plasticity and belongs to an easy-cracking alloy. In addition, the alloy belongs to a coarse-grained alloy, and the organizational uniformity is difficult to control, thereby affecting the mechanical properties. SUMMARY

[0004] In order to overcome the defects of the prior art, the purpose of the present application is to provide a preparation method of high-temperature alloy bar, which solves the technical problems that the GH4698 alloy has large deformation resistance and is easy to crack in the process, and the organizational uniformity is difficult to control. Through optimization of the deformation mode, the organizational uniformity of the bar is improved, and the anisotropy of the bar is reduced. The low-magnification organization of the Φ200mm to 300mm large-size bar is uniform, the grain size is 3 to 4 levels, the carbide distribution is more uniform, the transverse performance of the bar after heat treatment is improved, the transverse and longitudinal performances can meet the corresponding standard requirements, and the preparation method has wide applicability in the field of GH4698 alloy preparation. The preparation method of the high-temperature alloy bar adopts the "transverse elongation" forging method, and the used raw material ingot is subjected to high-temperature homogenization.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: a preparation method of high-temperature alloy bar, comprising the following steps:

[0006] Step 1, the heating temperature of the breakdown forging is 1150 DEG C to 1180 DEG C, the breakdown forging is the first heat, the ingot is subjected to homogenization heat treatment before the breakdown forging, the axial upsetting and drawing deformation is carried out on the 8000T fast forging machine, the deformation amount of the upsetting and drawing is 10% to 30%, the deformation amount of each pass is not greater than 10%, and the surface temperature of the blank after the forging is greater than 900 DEG C.

[0007] Step 2, the heating temperature of the second heating is 1150-1180℃, upsetting deformation is carried out on the 8000T fast forging machine, the upsetting deformation is 20-40%, the deformation of each pass is not more than 15%, the surface temperature of the blank after forging is greater than 900℃;

[0008] Step 3, the heating temperature of the third heating is 1080-1120℃, upsetting deformation is carried out on the 8000T fast forging machine, the upsetting deformation is 20-40%, the deformation of each pass is not more than 15%, the surface temperature of the blank after forging is greater than 800℃;

[0009] Step 4, the heating temperature of the fourth heating is 1080-1120℃, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation is 25-45%, the deformation of each pass is not more than 20%, the surface temperature of the blank after forging is greater than 800℃;

[0010] Step 5, the heating temperature of the fifth-sixth heating is 1080-1120℃, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation of each heating is 25-45%, the deformation of each pass is not less than 20%, the surface temperature of the blank after forging is greater than 800℃;

[0011] Step 6, the heating temperature of the seventh heating is 1060-1100℃, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation is 25-45%, the deformation of each pass is not less than 20%, the surface temperature of the blank after forging is greater than 800℃;

[0012] Step 7, the heating temperature of the eighth heating is 1060-1100℃, round deformation is carried out on the 8000T fast forging machine, the round deformation is 10-20%, the deformation of each pass is not more than 5%, fast high-frequency forging is required, the surface temperature of the blank after forging is greater than 800℃.

[0013] The heating temperature in step 1 is 1165-1180℃, the temperature is kept for 3-4 hours, the surface temperature of the blank after forging is greater than 900℃ and less than 1000℃.

[0014] The heating temperature in step 2 is 1150-1175℃, the temperature is kept for 2-3 hours, the blank is axially upset forged, the upsetting deformation is 30-40%, the deformation of each pass is 5-15%, the surface temperature of the blank after forging is greater than 900℃ and less than 1000℃.

[0015] The heating temperature in step 3 is 1090-1110 DEG C, heating and keeping for 2-3 hours, axial upsetting forging of the blank, the deformation of upsetting is 30-40%, the deformation of each pass is 5-15%, and the surface temperature of the blank after forging is greater than 800 DEG C and less than 900 DEG C.

[0016] In step 4, heating and keeping for 1.5-2.5 hours, radial elongation deformation is carried out on an 8000T fast forging machine, the deformation is controlled to be 35-45%, the deformation of each pass is 10-20%, and the surface temperature of the blank after forging is greater than 800 DEG C and less than 900 DEG C.

[0017] In step 5, the heating temperature is 1090-1110 DEG C, heating and keeping for 1.5-2.5 hours, elongation is carried out on an 8000T fast forging machine, the deformation of each pass is 20-25%, and the surface temperature of the blank after forging is greater than 800 DEG C and less than 900 DEG C.

[0018] In step 6, the heating temperature is 1080 DEG C±10 DEG C, heating and keeping for 1-2 hours, elongation is carried out on an 8000T fast forging machine, the deformation of each pass is 20-25%, and the surface temperature of the blank after forging is greater than 800 DEG C and less than 900 DEG C.

[0019] In step 7, falling round is carried out on an 8000T fast forging machine, the pressing amount of each hammer is controlled, and the surface temperature of the blank after forging is greater than 800 DEG C.

[0020] The GH4698 high-temperature alloy rod prepared by the preparation method of the high-temperature alloy rod has a specification of Φ200mm-300mm, the macrostructure of the rod is uniform, and the grain size reaches 3-4 levels.

[0021] Compared with the prior art, the application has the following beneficial technical effects:

[0022] The preparation method of the high-temperature alloy rod uses a fast forging machine to produce a Φ200mm-300mm specification GH4698 high-temperature alloy rod, optimizes the deformation mode, improves the uniformity of the rod, reduces the anisotropy of the rod, improves the transverse performance of the rod after heat treatment, and meets the corresponding standard requirements in the transverse and longitudinal directions, successfully breaks through the performance requirements and the uniformity requirements of the GH4698 high-temperature alloy rod. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a macrostructure (transverse direction) schematic diagram of the Φ200mm specification GH4698 rod of the application.

[0024] Figure 2 It is a macrostructure (transverse direction) schematic diagram of the Φ200mm specification GH4698 rod of the application.

[0025] Figure 3 Figure 1 is a schematic diagram of the high-magnification structure (longitudinal direction) of the 1 / 2R of the Φ200mm GH4698 rod of the present application.

[0026] Figure 4 Figure 2 is a schematic diagram of the high-magnification structure (longitudinal direction) of the core of the Φ200mm GH4698 rod of the present application.

[0027] Figure 5 Figure 3 is a schematic diagram of the low-magnification (transverse direction) of the Φ250mm GH4698 rod of the present application.

[0028] Figure 6 Figure 4 is a schematic diagram of the high-magnification structure (longitudinal direction) of the edge of the Φ250mm GH4698 rod of the present application.

[0029] Figure 7 Figure 5 is a schematic diagram of the high-magnification structure (longitudinal direction) of the 1 / 2R of the Φ250mm GH4698 rod of the present application.

[0030] Figure 8 Figure 6 is a schematic diagram of the high-magnification structure (longitudinal direction) of the core of the Φ250mm GH4698 rod of the present application. DETAILED DESCRIPTION

[0031] The present application will be further described in detail below in connection with specific examples.

[0032] The method for preparing the high-temperature alloy rod of the present application adopts the "transverse elongation" forging method, and the raw material ingot is subjected to high-temperature homogenization. The method specifically comprises the following steps:

[0033] Step 1, the heating temperature of the breakdown forging is 1150-1180℃, the breakdown forging is the first fire, the ingot is subjected to homogenization heat treatment before the breakdown forging, axial upsetting and drawing deformation is performed on the 8000T fast forging machine, the deformation amount of the upsetting and drawing is 10-30%, the deformation amount of each pass is not greater than 10%, and the surface temperature of the blank after the forging is greater than 900℃;

[0034] Step 2, the heating temperature of the second fire is 1150-1180℃, upsetting deformation is performed on the 8000T fast forging machine, the deformation amount of the upsetting is 20-40%, the deformation amount of each pass is not greater than 15%, and the surface temperature of the blank after the forging is greater than 900℃;

[0035] Step 3, the heating temperature of the third fire is 1080-1120℃, upsetting deformation is performed on the 8000T fast forging machine, the deformation amount of the upsetting is 20-40%, the deformation amount of each pass is not greater than 15%, and the surface temperature of the blank after the forging is greater than 800℃;

[0036] Step 4, the heating temperature of the 4th heating is 1080-1120 DEG C, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation amount is 25-45%, the deformation amount of each pass is not more than 20%, and the surface temperature of the blank after forging is greater than 800 DEG C;

[0037] Step 5, the heating temperature of the 5th-6th heating is 1080-1120 DEG C, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation amount is 25-45%, the deformation amount of each pass is not less than 20%, and the surface temperature of the blank after forging is greater than 800 DEG C;

[0038] Step 6, the heating temperature of the 7th heating is 1060-1100 DEG C, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation amount is 25-45%, the deformation amount of each pass is not less than 20%, and the surface temperature of the blank after forging is greater than 800 DEG C;

[0039] Step 7, the heating temperature of the 8th heating is 1060-1100 DEG C, radial elongation deformation is carried out on the 8000T fast forging machine, the elongation deformation amount is 25-45%, the deformation amount of each pass is not less than 20%, and the surface temperature of the blank after forging is greater than 800 DEG C.

[0040] Example one

[0041] The preparation method of the high-temperature alloy rod of the application comprises the following steps:

[0042] Step 1, the heating temperature of the blooming forging is 1165 DEG C, the ingot has completed the homogenization heat treatment before the blooming forging, the 8000T fast forging machine is used to carry out the blooming forging on the ingot of the specification of Ф490mm, the ingot is upset and drawn to the square billet of the specification of eight sides 425xL after one heating and drawing, the deformation mode is one upsetting and one drawing, the deformation amount of the upsetting and elongation is 20%, the deformation amount of each pass is 7%, the surface temperature of the blank after forging is 953 DEG C, the blank is returned to the furnace for temperature compensation after forging, and the next heating is carried out;

[0043] Step 2, the second heating is carried out on the 8000T fast forging machine to carry out the upsetting deformation on the square billet of the specification of eight sides 425xL to the square billet of the specification of eight sides 530xL, the heating temperature is 1165 DEG C, the deformation mode is one upsetting, the deformation amount of the upsetting is 30%, the deformation amount of each pass is 10%, the surface temperature of the blank after forging is 961 DEG C, the blank is returned to the furnace for temperature compensation after forging, and the next heating is carried out;

[0044] Step 3, the third fire is on the 8000T fast forging machine to the eight party 530xL specification square billet is up to the specification of eight party 660xL specification square billet, the heating temperature is 1100 DEG C, the deformation mode is one upset, the deformation of upsetting is 30%, the deformation of each pass is 10%, the surface temperature of the billet after forging is 865 DEG C, the billet is returned to the furnace after forging to supplement the temperature, and the next fire forging is carried out;

[0045] Step 4, the fourth fire is on the 8000T fast forging machine to the eight party 660xL specification square billet is elongated to the specification of eight party 510xL square billet, the heating temperature is 1100 DEG C, the elongation deformation is 35%, the surface temperature of the billet after forging is 853 DEG C, the deformation of each pass is 15%, the billet is returned to the furnace after forging to supplement the temperature, and the next fire forging is carried out;

[0046] Step 5, the fifth and sixth fires are on the 8000T fast forging machine to the eight party 510xL specification square billet is elongated to the specification of eight party 305xL square billet, the heating temperature is 1100 DEG C, the deformation of each fire is 35%, the deformation of each pass is 25%, the surface temperature of the billet after forging is 848 DEG C, the billet is returned to the furnace after forging to supplement the temperature, and the next fire forging is carried out;

[0047] Step 6, the seventh fire is on the 8000T fast forging machine to the eight party 305xL specification square billet is elongated to the specification of eight party 230xL square billet, the heating temperature is 1080 DEG C, the elongation deformation is 35%, the deformation of each pass is 25%, the surface temperature of the billet after forging is 851 DEG C, the billet is returned to the furnace after forging to supplement the temperature, and the next fire forging is carried out;

[0048] Step 7, the eighth fire is on the 8000T fast forging machine to the eight party 230xL square billet is elongated to the specification of eight party 230xL square billet, the heating temperature is 1080 DEG C, the elongation deformation is 15%, the deformation of each pass is 3%, the stroke of each hammer is controlled, and the finished product specification is Φ200mm rod.

[0049] Example two

[0050] The preparation method of the high-temperature alloy rod of the application comprises the following steps:

[0051] Step 1, the opening billet ingot specification is Ф508mm, the heating temperature of the opening forging is 1150 DEG C, the holding time is 3 hours, the ingot has been uniformly treated before the opening forging, one upsetting and one elongation are carried out on the ingot, the deformation of upsetting and elongation is 10%, the deformation of each pass is controlled to be 5%, the surface temperature of the billet after forging is 908 DEG C, the billet is returned to the furnace after forging to supplement the temperature, and the next fire forging is carried out;

[0052] Step 2, the heating temperature is 1150 DEG C, the holding time is 2 hours, one upsetting forging is carried out, the upsetting deformation is controlled to be 20%, the deformation of each pass is 5%, the surface temperature of the billet after forging is 905 DEG C;

[0053] Step 3: heating at 1080℃ for 2 hours, axial upsetting forging is performed, and the deformation amount is controlled to be 20%, and the deformation amount of each pass is 5%;

[0054] Step 4: heating at 1080℃ for 2 hours, radial elongation forging is performed, and the deformation amount is controlled to be 25%, and the deformation amount of each pass is 10%;

[0055] Step 5: heating at 1080℃ for 1.5 hours, elongation forging is performed, and the deformation amount is controlled to be 25%, and the deformation amount of each pass is 20%; heating at 1080℃ for 1.5 hours, elongation forging is performed, and the deformation amount is controlled to be 25%, and the deformation amount of each pass is 20%, after each forging, the billet surface temperature is allowed to be reheated, and then the next forging is performed, and after the forging is completed, the billet surface temperature is 806℃;

[0056] Step 6: heating at 1060℃ for 1.5 hours, elongation forging is performed, and the deformation amount is controlled to be 25%, and the deformation amount of each pass is 20%, and after the forging is completed, the billet surface temperature is 809℃;

[0057] Step 7: the billet is heated at 1060℃, and drop round forging is performed, and the drop round forging deformation amount is controlled to be 10%, and after the forging is completed, the billet surface temperature is 802℃, and the reduction amount gradually decreases during the forming process, and the finished size of the rod is Φ250mm, and air cooling is adopted after the forging.

[0058] Example three:

[0059] The preparation method of the high-temperature alloy rod according to the present application comprises the following steps:

[0060] In step 1, the heating temperature of the first heating is 1180℃, the deformation amount of upsetting and elongation is 30%, and the deformation amount of each pass is 10%, and after the forging is completed, the billet surface temperature is 980℃.

[0061] In step 2, the heating temperature of the second heating is 1180℃, axial upsetting forging is performed on the billet, the deformation amount of upsetting is 40%, and the deformation amount of each pass is 15%, and after the forging is completed, the billet surface temperature is 995℃;

[0062] In step 3, the heating temperature of the third heating is 1120℃, axial upsetting forging is performed on the billet, the deformation amount of upsetting is 40%, and the deformation amount of each pass is 15%, and after the forging is completed, the billet surface temperature is 894℃;

[0063] In step 4, the heating temperature of the fourth heating is 1120℃, radial elongation forging is performed on the billet, and the deformation amount of elongation is 45%, and the deformation amount of each pass is 20%, and after the forging is completed, the billet surface temperature is 890℃;

[0064] The temperature of the 5th-6th heating in step 5 is 1120 DEG C, and the elongation deformation is carried out on the 8000T fast forging machine, the deformation amount of each heating is controlled to be 45%, and the deformation amount of each pass is 30%, and the surface temperature of the blank after forging is 885 DEG C;

[0065] The temperature of the 7th heating in step 6 is 1100 DEG C, and the elongation deformation is carried out on the 8000T fast forging machine, the deformation amount of each heating is controlled to be 45%, and the deformation amount of each pass is 30%, and the surface temperature of the blank after forging is 872 DEG C;

[0066] The temperature of the 8th heating in step 7 is 1100 DEG C, and the elongation deformation is carried out on the 8000T fast forging machine, the deformation amount of each heating is controlled to be 45%, and the deformation amount of each pass is 30%, and the surface temperature of the blank after forging is 872 DEG C;

[0067] Example four: performance test of GH4698 high-temperature alloy rod prepared by the method of the application

[0068] A plurality of batches of products are produced by the method of the application, and the mechanical property data of 2 batches of GH4698 high-temperature alloy rods with specifications of Φ200mm and Φ250mm are shown in Table 1.

[0069] As shown in Table 1, the longitudinal performance meets the standard requirements, and the surplus amount is relatively large; the transverse performance also meets the requirements, and the room plasticity surplus amount is relatively small, and the remaining performance has a certain surplus amount.

[0070] Table 1: Mechanical properties of GH4698 high-temperature alloy rod

[0071]

[0072] As shown in Table 1 and Figures 1-8 The results show that the GH4698 high-temperature alloy large-size rod produced by the forging process of the application has uniform structure, the transverse macrostructure of the rod is uniform and fuzzy, and there are no metallurgical defects such as shrinkage, cracks and slag inclusion; the longitudinal microstructure of different parts is relatively uniform and fine, and the average grain size is 3-4 levels. The performance test results completely meet the standard requirements.

[0073] In summary, the application can be well implemented, and the above examples only describe the preferred embodiments of the application, and do not limit the scope of the application. Various modifications and improvements of the technical solutions of the application made by those skilled in the art without departing from the design spirit of the application shall fall within the scope of protection of the application.

Claims

1. A method of producing a high temperature alloy bar, characterized by, It comprises the following steps: Step 1, the heating temperature of the cogging forging is 1150-1180 DEG C, the cogging forging is the first heating, the ingot is uniformly treated before the cogging forging, the axial upsetting and drawing deformation is carried out on the 8000T fast forging machine, the upsetting and drawing deformation is 10-30%, the deformation of each pass is not more than 10%, and the surface temperature of the blank after the forging is greater than 900 DEG C; Step 2, the heating temperature of the second heating is 1150-1180 DEG C, the upsetting deformation is carried out on the 8000T fast forging machine, the upsetting deformation is 20-40%, the deformation of each pass is not more than 15%, and the surface temperature of the blank after the forging is greater than 900 DEG C; Step 3, the heating temperature of the third heating is 1080-1120 DEG C, the upsetting deformation is carried out on the 8000T fast forging machine, the upsetting deformation is 20-40%, the deformation of each pass is not more than 15%, and the surface temperature of the blank after the forging is greater than 800 DEG C; Step 4, the heating temperature of the fourth heating is 1080-1120 DEG C, the radial drawing deformation is carried out on the 8000T fast forging machine, the drawing deformation is 25-45%, the deformation of each pass is not more than 20%, and the surface temperature of the blank after the forging is greater than 800 DEG C; Step 5, the heating temperature of the fifth-sixth heating is 1080-1120 DEG C, the radial drawing deformation is carried out on the 8000T fast forging machine, the deformation of each heating is 25-45%, the deformation of each pass is not less than 20%, and the surface temperature of the blank after the forging is greater than 800 DEG C; Step 6, the heating temperature of the seventh heating is 1060-1100 DEG C, the radial drawing deformation is carried out on the 8000T fast forging machine, the drawing deformation is 25-45%, the deformation of each pass is not less than 20%, and the surface temperature of the blank after the forging is greater than 800 DEG C; Step 7, the heating temperature of the eighth heating is 1060-1100 DEG C, the upsetting deformation is carried out on the 8000T fast forging machine, the upsetting deformation is 10-20%, the deformation of each pass is not more than 5%, the fast high-frequency forging is required, and the surface temperature of the blank after the forging is greater than 800 DEG C.

2. A method of producing a high temperature alloy bar according to claim 1, characterized in that, The heating temperature in the step 1 is 1165-1180 DEG C, the temperature is kept for 3-4 hours, and the surface temperature of the blank after the forging is greater than 900 DEG C and less than 1000 DEG C.

3. The method of claim 1, wherein the high temperature alloy bar is prepared by the steps of: The heating temperature in the step 2 is 1150-1175 DEG C, the temperature is kept for 2-3 hours, the blank is axially upset forged, the upsetting deformation is 30-40%, the deformation of each pass is 5-15%, and the surface temperature of the blank after the forging is greater than 900 DEG C and less than 1000 DEG C. ​ 4. The method of claim 1, wherein the high temperature alloy bar is prepared by the steps of: The heating temperature in the step 3 is 1090-1110 DEG C, the temperature is kept for 2-3 hours, the blank is axially upset forged, the upsetting deformation is 30-40%, the deformation of each pass is 5-15%, and the surface temperature of the blank after the forging is greater than 800 DEG C and less than 900 DEG C.

5. The method of claim 1, wherein the high temperature alloy bar is prepared by the steps of: The step 4 is heated and kept for 1.5-2.5 hours, and then radial elongation deformation is carried out on the 8000T fast forging machine, the deformation amount is controlled to be 35%-45%, the deformation amount of each pass is 10%-20%, and the surface temperature of the blank after forging is greater than 800℃ and less than 900℃. ​ 6. The method of claim 1, wherein the high temperature alloy bar is prepared by the steps of: The step 5 is heated at 1090-1110℃, heated and kept for 1.5-2.5 hours, elongation is carried out on the 8000T fast forging machine, the deformation amount of each pass is 20%-25%, and the surface temperature of the blank after forging is greater than 800℃ and less than 900℃.

7. The method of claim 1, wherein the high temperature alloy bar is prepared by the steps of: The heating temperature in the step 6 is 1080℃±10℃, heated and kept for 1-2 hours, elongation is carried out on the 8000T fast forging machine, the deformation amount of each pass is 20%-25%, and the surface temperature of the blank after forging is greater than 800℃ and less than 900℃. ​

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