Preparation method of GH4141 high-temperature alloy with carbide separated out along grain boundary

Abstract

The invention relates to a preparation method of a GH4141 high-temperature alloy with carbide separated out along a grain boundary. The preparation method comprises the following steps: firstly, carrying out solid solution heat treatment on a GH4141 high-temperature alloy material, heating along with a furnace at a heating rate of 8-10 DEG C / min, keeping the temperature at 1100-1140 DEG C for 30-40 minutes, and carrying out air cooling to room temperature; then the solid solution material is subjected to aging heat treatment, furnace heating is conducted, the heating rate is 8-10 DEG C / min, heat preservation is conducted for 60-70 min at the temperature of 880-920 DEG C, and air cooling is conducted to the room temperature; according to the method, precipitation and distribution of the carbides are accurately regulated and controlled through the temperature and the time, the carbides can be all precipitated and distributed along the grain boundary, the M23C6 type carbides are not precipitated along the grain boundary, the method also has an obvious effect on materials with different deformation amounts, and the process applicability is high.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of high-temperature alloy processing, and particularly relates to a preparation method of a GH4141 high-temperature alloy with carbide precipitated along grain boundaries. BACKGROUND

[0002] As a new type of nickel-based wrought high-temperature alloy, the GH4141 high-temperature alloy can meet the manufacturing requirements of high-strength components at a high temperature of 870 DEG C, and can still maintain excellent oxidation resistance under a working condition below 980 DEG C. Compared with the widely used GH4169 high-temperature alloy, the upper limit of the service temperature of the material is increased by more than 200 DEG C, and the material is a candidate material for hot end components such as blades, turbine discs and casings of an aero-engine. The performance of the GH4141 high-temperature alloy is largely dependent on the microstructure of the material, which contains MC, M6C and M 23 C6 three types of carbides and a nanoscale γ' precipitated strengthening phase. The carbides mainly affect the hardness and strength of the alloy. At present, the preparation process of the GH4141 high-temperature alloy is also focused on the regulation and control of key parameters such as homogenization treatment, solid solution temperature and time, aging temperature and time on the microstructure in the heat treatment process. The existing technology shows that the precipitation behavior of the carbide along the grain boundaries has a significant influence on the performance of the alloy: the moderate dispersion distribution of the carbide along the grain boundaries can effectively improve the strength and hardness of the alloy, but the uncontrolled precipitation form and distribution state of the carbide will cause a sharp increase in the brittleness of the material, resulting in serious deterioration of the plasticity and toughness indexes. It is particularly worth noting that the continuous precipitation of the lamellar M 23 C6 carbide at the grain boundaries has been confirmed as the core inducement of the alloy brittleness (Peitao, Chen Sibo, Zhang Weihong, et al. Influence of γ' phase precipitation on the precipitation of lamellar M23C6 phase in GH4145 alloy [J]. Aviation Manufacturing Technology, 2020, 63(3): 92-95, 102. DOI:10.16080 / j.issn1671-833x.2020.03.092.). However, the current conventional heat treatment process is difficult to realize the precise control of the precipitation and spatial distribution of the carbide due to the insufficient parameter matching, so that the grain boundary brittle phase is difficult to eliminate, which seriously restricts the engineering application reliability of the alloy in a high-temperature and high-stress environment.

[0003] In view of the above challenges, it is urgent to explore a new heat treatment process method to realize the precise control of the carbide in the microstructure of the alloy, so as to guide the actual production. SUMMARY

[0004] In order to overcome the shortcomings of the above existing technology, the purpose of the present application is to provide a preparation method of a GH4141 high-temperature alloy with carbide precipitated along grain boundaries, which realizes the precipitation and distribution of the carbide along the grain boundaries by precisely regulating and controlling the precipitation and distribution of the carbide through temperature and time, so that the M 23The C6 type carbide grain boundary is precipitated, and the method has obvious effects on materials with different deformation amounts, and has strong process applicability.

[0005] In order to achieve the above object, the present application adopts the following technical scheme: A preparation method of GH4141 high-temperature alloy with carbide precipitated along grain boundaries comprises the following steps: Step one: solid solution heat treatment is carried out on the GH4141 high-temperature alloy material, furnace heating is carried out, the heating rate is 8-10 ℃ / min, the temperature is kept at 1100-1140 ℃ for 30-40 min, and air cooling is carried out to room temperature. Step two: the solid solution material obtained in step one is subjected to aging heat treatment, furnace heating is carried out, the heating rate is 8-10 ℃ / min, the temperature is kept at 880-920 ℃ for 60-70 min, and air cooling is carried out to room temperature.

[0006] The preparation method of the GH4141 high-temperature alloy with carbide precipitated along grain boundaries has effects on the precipitation and distribution of carbides in GH4141 high-temperature alloys with different deformation amounts, induces MC and M6C carbides in the GH4141 high-temperature alloy to precipitate along grain boundaries, and M 23 The C6 type carbide grain boundary is precipitated, and the method has important significance for improving the plasticity and toughness of the alloy.

[0007] The different deformation amounts are strain amounts of 0.2-0.8.

[0008] Compared with the prior art, the present application has the following beneficial effects: 1) The present application can effectively induce MC and M6C carbides in the GH4141 high-temperature alloy to precipitate and distribute along grain boundaries, realize the M 23 The C6 type carbide is not precipitated, and has important significance for improving the plasticity and toughness of the alloy.

[0009] 2) The method has strong applicability, has effects on the precipitation and distribution of carbides in GH4141 high-temperature alloys with different deformation amounts, can effectively induce MC and M6C carbides in the GH4141 high-temperature alloy to precipitate along grain boundaries, and M 23 The C6 type carbide grain boundary is precipitated, and the method has important significance for improving the plasticity and toughness of the alloy.

[0010] 3) The method has short process time and remarkable effect, can greatly improve the production efficiency, and has obvious production guiding value for high-temperature alloys which are materials with extremely high manufacturing cost. DETAILED DESCRIPTION

[0011] Figure 1 The figure is a carbide precipitation and distribution graph of undeformed GH4141 high-temperature alloy after example 1.

[0012] Figure 2Carbide precipitation distribution map of GH4141 superalloy after Example 2, Example 3, Example 4, where a) strain amount 0.2; b) strain amount 0.4; c) strain amount 0.8.

[0013] Figure 3 Carbide precipitation distribution map of GH4141 superalloy after Comparative Example 1, Comparative Example 2, where a) un-deformed; b) strain amount 0.8. DETAILED DESCRIPTION

[0014] The application will be further described below in conjunction with the examples and drawings. It should be particularly noted that the examples described below are only typical cases of the technical solutions of the application, and the purpose is to clearly explain the core principles and technical features of the application, and do not constitute a limiting interpretation of the scope of the claims.

[0015] Example 1, the un-deformed sample cut from GH4141 superalloy was subjected to solid solution treatment, furnace heating, heating rate 10℃ / min, to 1120℃ temperature for 30min, then immediately removed and air cooled to room temperature; then subjected to aging treatment, furnace heating, heating rate 10℃ / min, to 900℃ temperature for 60min, then immediately removed and air cooled to room temperature.

[0016] As shown in Figure 1 , the MC and M6C carbides of the GH4141 superalloy treated by this embodiment are both distributed along the grain boundaries, the MC carbides are irregular blocks, the M6C carbides are continuously precipitated along the grain boundaries, showing long chains, and there is no M 23 C6 type carbide precipitation at the grain boundaries.

[0017] Example 2, the same batch of GH4141 superalloy material as in Example 1 was used, and hot deformation was carried out at a strain rate of 0.01s -1 , strain amount 0.2, deformation temperature 1100℃, and the deformed material was subjected to solid solution treatment, furnace heating, heating rate 8℃ / min, to 1100℃ temperature for 30min, then immediately removed and air cooled to room temperature; then subjected to aging treatment, furnace heating, heating rate 8℃ / min, to 880℃ temperature for 60min, then immediately removed and air cooled to room temperature.

[0018] Example 3, the same batch of GH4141 superalloy material as in Example 1 was used, and hot deformation was carried out at a strain rate of 0.01s -1The strain was 0.4, and the deformation temperature was 1100℃. The deformed material was then subjected to solution treatment and heated in the furnace at a rate of 9℃ / min. After reaching 1120℃, the temperature was held for 35 minutes, and then immediately removed and air-cooled to room temperature. Subsequently, aging treatment was performed, and the material was heated in the furnace at a rate of 9℃ / min. After reaching 900℃, the temperature was held for 65 minutes, and then immediately removed and air-cooled to room temperature.

[0019] Example 4 uses the same GH4141 high-temperature alloy material as in Example 1, with a strain rate of 0.01s. -1 The strain was 0.8, and the deformation temperature was 1100℃. The deformed material was then subjected to solution treatment and heated in the furnace at a rate of 10℃ / min. After reaching 1140℃, the temperature was held for 40 minutes, and then immediately removed and air-cooled to room temperature. Subsequently, aging treatment was performed, and the material was heated in the furnace at a rate of 10℃ / min. After reaching 920℃, the temperature was held for 70 minutes, and then immediately removed and air-cooled to room temperature.

[0020] like Figure 2 As shown, under different deformation amounts, the treatments in Examples 2, 3, and 4 can effectively induce the precipitation of MC and M6C carbides along grain boundaries in the GH4141 high-temperature alloy. 23 No C6 type carbides were precipitated.

[0021] Comparative Example 1: The same batch of GH4141 high-temperature alloy material as in Example 1 was used. The material was subjected to solution treatment and heated in the furnace at a heating rate of 10°C / min. After reaching a temperature of 1190°C, it was held for 30 minutes and then immediately removed and air-cooled to room temperature. Subsequently, aging treatment was performed, with the material being heated in the furnace at a heating rate of 10°C / min. After reaching a temperature of 900°C, it was held for 60 minutes and then immediately removed and air-cooled to room temperature.

[0022] Comparative Example 2 used the same GH4141 high-temperature alloy material as Example 1, with a strain rate of 0.01 s⁻¹. -1 The strain was 0.8, and the deformation temperature was 1100℃. The deformed material was then subjected to solution treatment and heated in the furnace at a rate of 10℃ / min. After reaching 1190℃, the temperature was held for 30 minutes, and then immediately removed and air-cooled to room temperature. Subsequently, aging treatment was performed, and the material was heated in the furnace at a rate of 10℃ / min. After reaching 900℃, the temperature was held for 60 minutes, and then immediately removed and air-cooled to room temperature.

[0023] like Figure 3 As shown, after treatment in Comparative Examples 1 and 2, some MC carbides in the GH4141 high-temperature alloy precipitated within the grains and some precipitated at the grain boundaries, while M6C carbides precipitated along the grain boundaries. 23 No C6 type carbides were precipitated.

[0024] The present application solid solution treatment partially dissolves MC carbide at high temperature (1100-1140℃) and inhibits its coarsening, while fully solid-solubilizing Cr element in the matrix, avoiding M 23 C6 nucleation; the aging treatment promotes the incoherent precipitation of M6C carbide at medium temperature holding (880-920℃), and makes it preferentially distributed along the grain boundaries by the slow diffusion characteristics of Mo / W; although the aging temperature is in the stable interval of M 23 C6 (500-900℃), but because Cr is locked in the matrix at the solid solution stage, and the diffusion of Cr is limited at low temperature, the nucleation driving force of M 23 C6 is significantly reduced.

Claims

1. A method for preparing GH4141 high-temperature alloy with carbide precipitation along grain boundaries, characterized in that, Includes the following steps: Step 1: Perform solution heat treatment on GH4141 high-temperature alloy material, heating in the furnace at a rate of 8~10℃ / min, holding at 1100~1140℃ for 30~40min, and then air cooling to room temperature; Step 2: The solid solution material obtained in Step 1 is subjected to aging heat treatment. It is heated in the furnace at a rate of 8~10℃ / min and held at 880~920℃ for 60~70min, and then air-cooled to room temperature.

2. The method according to claim 1, characterized in that: It has the effect on the precipitation and distribution of carbides in GH4141 superalloy with different deformation amounts, inducing the precipitation of MC and M6C carbides along grain boundaries in GH4141 superalloy. 23 C6 type carbide grain boundaries are present in very small amounts or even not at all.

3. The method according to claim 1, characterized in that: The different deformation amounts mentioned are strains of 0.2-0.8.

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