CN-117802337-B - Preparation method of high-temperature alloy

CN117802337BCN 117802337 BCN117802337 BCN 117802337BCN-117802337-B

Abstract

The invention discloses a preparation method of a high-temperature alloy, which comprises the following steps of (1) mixing high-temperature alloy raw material powder and a granulating agent for granulating to obtain a granulating raw material, and (2) sintering the granulating raw material under a vacuum condition by using oscillation hot-pressing, wherein an alternating load is adopted during sintering to control the growth process of crystal grains, so that the high-temperature alloy is obtained. The preparation method of the high-temperature alloy comprises the steps of firstly granulating alloy powder, and then controlling the grain growth process of the product by controlling the alternating load of the oscillating thermal sintering process, thereby being beneficial to grain refinement, generating fine grain strengthening effect and greatly improving the mechanical property of the high-temperature alloy product. And through the mutual synergistic effect of granulation and alternating load, the density of the product can be improved.

Inventors

CHEN JINGWEI
FAN YAN
SHENG LIWEN
SHENG JIANHUA
Hou Shangdong
JIANG KANGHE

Assignees

株洲万融新材科技有限公司
中国航发湖南动力机械研究所

Dates

Publication Date: 20260508
Application Date: 20220923

Claims (5)

1. The preparation method of the high-temperature alloy is characterized by comprising the following steps of: (1) Mixing high-temperature alloy raw material powder with a granulating agent for granulating to obtain a granulating raw material; (2) Under the vacuum condition, the high-temperature alloy is obtained by using oscillation hot-pressing sintering granulation raw materials and adopting alternating load to control the growth process of crystal grains during sintering; The high-temperature alloy raw material powder is FGH95, FGH96, FGH97 or FGH99, the granulating agent comprises one or more of polyethylene glycol, nitrocellulose, stearic acid or paraffin wax mixture, and the mass ratio of the high-temperature alloy raw material powder to the granulating agent is (95-99): 1-5; controlling the screen size so that the particle size of the granulated raw material is 50-150 μm; The oscillating hot-pressing sintering comprises a first degreasing sintering step and a second strengthening sintering step, and constant-temperature and constant-pressure heat treatment is adopted after the oscillating hot-pressing sintering step; The first degreasing sintering is carried out for 1-4 hours at 150-250 ℃, meanwhile, the bidirectional oscillation pressure with the pressure of 50-150MPa and the frequency of 2-15HZ is applied, and the vacuum degree is controlled at 10 -3 -10 -1 Pa; The second step of strengthening sintering is to heat-preserving for 2-10h at 1000-1300 ℃, and simultaneously, applying oscillation pressure with the pressure of 50-150MPa and the frequency of 2-15HZ, and controlling the vacuum degree at 10 -3 -10 -1 Pa.
2. The preparation method according to claim 1, wherein the granulating process comprises the steps of ball-milling and mixing the superalloy raw material powder, the granulating agent and the ethanol, vacuum-drying and sieving to complete the granulating.
3. The preparation method according to claim 2, wherein the mixing time is 2-6 hours during ball milling and the drying temperature is controlled to be 80-100 ℃ during vacuum drying.
4. The method according to claim 1, wherein the second step of the enhanced sintering includes a primary single/double-direction oscillating hot-pressing alternate process and a secondary low-frequency high-voltage/high-frequency low-voltage oscillating hot-pressing alternate process; the primary single/bidirectional oscillation hot pressing alternate process is that single/bidirectional oscillation hot pressing alternate process is adopted, the sintering temperature is 1000-1300 ℃, the sintering time is 1-5h, the pressure is 50-150MPa, the frequency is 2-15HZ, the vacuum degree is 10 -3 -10 -1 Pa, unidirectional oscillation hot pressing is firstly adopted, the unidirectional oscillation hot pressing duration is t1, the bidirectional synchronous oscillation hot pressing duration is t2, t1 is less than or equal to 20min, and t2 is less than or equal to 5min and less than or equal to 20min; The secondary low-frequency high-voltage/high-frequency low-voltage oscillation hot pressing alternating process adopts bidirectional oscillation hot pressing, adopts low-frequency high-voltage and high-frequency low-voltage alternating process, the sintering temperature is 1000-1300 ℃, the sintering time is 1-5h, the vacuum degree is 10 -3 -10 -1 Pa, the low-frequency high-voltage is firstly adopted, the low-frequency high-voltage duration is t3, the high-frequency low-voltage duration is t4, the time is less than or equal to 5min and less than or equal to 3 and less than or equal to 20min, the time is less than or equal to 5min and less than or equal to 4 and less than or equal to 20min, the sintering pressure is 120-150MPa, the frequency is 2-8HZ, the sintering pressure is 50-80MPa, and the frequency is 12-15HZ when the sintering pressure is high-frequency low.
5. The preparation method according to claim 1, wherein the constant temperature and constant pressure heat treatment is to heat the furnace to 1150-1350 ℃ first, then put the sample subjected to the oscillation hot-pressed sintering into the furnace, heat treat at 60-80MPa for 1-6 hours at constant temperature and constant pressure, and then take out for cooling in an air cooling or quenching mode.

Description

Preparation method of high-temperature alloy Technical Field The invention belongs to the field of alloy materials, and particularly relates to a processing method of a high-temperature alloy. Background At present, in the field of aeroengines, turbine discs are usually prepared from high-temperature alloys, and the aviation industry has urgent demands for improving the production efficiency of the turbine discs and reducing the preparation cost. The traditional powder superalloy preparation adopts the technological process of Hot Isostatic Pressing (HIP) forming and sheath/heat treatment, the technology is to form in hot isostatic pressing equipment with the pressure of more than 1200 atmospheres, the procedures are multiple, the time and energy consumption are long, the equipment is complex, the high-pressure equipment is adopted, the danger is high, the expansion limit is more, and the cost is high. In addition, the mechanical properties of the superalloy prepared by the above technique are to be further enhanced. Therefore, the preparation method of the high-temperature alloy with simple process, simple equipment, high safety coefficient and excellent mechanical property has wide market application prospect. Disclosure of Invention The invention aims to overcome the defects and the shortcomings in the background art and provide a preparation method of high-temperature alloy with excellent mechanical properties. In order to solve the technical problems, the technical scheme provided by the invention is as follows: A preparation method of a high-temperature alloy comprises the following steps: (1) Mixing high-temperature alloy raw material powder with a granulating agent for granulating to obtain a granulating raw material; (2) And under the vacuum condition, sintering the granulating raw materials by using oscillation hot-pressing, wherein an alternating load is adopted during sintering to control the growth process of crystal grains, and the high-temperature alloy is obtained. In the preparation method, preferably, the high-temperature alloy raw material powder comprises FGH95, FGH96, FGH97 or FGH99, the granulating agent comprises one or more of polyethylene glycol, nitrocellulose, stearic acid or paraffin wax mixture, and the mass ratio of the high-temperature alloy raw material powder to the granulating agent is (95-99): 1-5. In the preparation method, the granulating process preferably comprises the steps of ball-milling and mixing high-temperature alloy raw material powder, a granulating agent and ethanol, and then vacuum drying and sieving to complete granulating. In the preparation method, the mixing time is preferably 2-6h during ball milling and mixing, and the drying temperature is preferably 80-100 ℃ during vacuum drying. In the above production method, preferably, the screen size is controlled so that the particle size of the granulated raw material is 50 to 150 μm at the time of sieving. In the above preparation method, preferably, the oscillating hot-press sintering includes a first degreasing sintering step and a second strengthening sintering step, and the oscillating hot-press sintering is followed by a constant-temperature and constant-pressure heat treatment. In the above preparation method, preferably, the first step of degreasing sintering is to keep the temperature at 150-250 ℃ for 1-4h, and simultaneously apply a bidirectional oscillating pressure with the pressure of 50-150MPa and the frequency of 2-15HZ, and the vacuum degree is controlled at 10 -3-10-1 Pa. In the above preparation method, preferably, the second step of strengthening sintering is to keep the temperature at 1000-1300 ℃ for 2-10h, and simultaneously apply an oscillating pressure with the pressure of 50-150MPa and the frequency of 2-15HZ, and the vacuum degree is controlled at 10 -3-10-1 Pa. In the above preparation method, preferably, the second step of enhanced sintering comprises a primary single/bidirectional oscillation hot pressing alternate process and a secondary low-frequency high-voltage/high-frequency low-voltage oscillation hot pressing alternate process, specifically, The primary single/bidirectional oscillation hot pressing alternate process is that single/bidirectional oscillation hot pressing alternate process is adopted, the sintering temperature is 1000-1300 ℃, the sintering time is 1-5h, the pressure is 50-150MPa, the frequency is 2-15HZ, the vacuum degree is 10 -3-10-1 Pa, unidirectional oscillation hot pressing is firstly adopted, the unidirectional oscillation hot pressing duration is t1, the bidirectional synchronous oscillation hot pressing duration is t2, t1 is less than or equal to 20min, and t2 is less than or equal to 5min and less than or equal to 20min; The secondary low-frequency high-voltage/high-frequency low-voltage oscillation hot pressing alternating process adopts bidirectional oscillation hot pressing, adopts low-frequency high-voltage and high-frequency low-voltage alternating