CN118814025A - In-situ self-generated TiC-Co3 (Al, Ti) synergistically reinforced high-temperature alloy composite material and preparation method - Google Patents

Abstract

The invention discloses an in-situ self-generated TiC- _Co3 (Al, Ti) synergistically reinforced high-temperature alloy composite material and a preparation method. First, a sintered sample is obtained by sintering _{Ti3AlC2 powder} and Co powder. The mass ratio of additionally added Ti and Al elements is calculated according to the composition of the sintered sample and the contents of Co, Al and Ti elements in the FCC_Al+FCC_L12 _dual- phase region in the Co-Al-Ti ternary alloy phase diagram. Then, after compensating with Ti powder and Al powder, the alloy composite material is obtained by sintering. During the sintering process, a process of _Ti3AlC2 forming TiC is generated. Finally, an FCC_L12 precipitation phase of _Co3 (Al, Ti) is obtained through aging treatment, thereby forming a high-temperature alloy composite material with two phases of synergistic reinforcement, namely, a TiC particle reinforcement phase and a _Co3 (Al, Ti) precipitation reinforcement phase.

Description

An in-situ self-generated TiC-Co3 (Al, Ti) synergistically reinforced high-temperature alloy composite material and preparation method

Technical Field

The present invention belongs to the technical field of material science, and in particular relates to an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material and a preparation method thereof.

Background Art

Compared with traditional Ni-based superalloys, Co-based superalloys have higher solidus and liquidus temperatures, higher high-temperature strength, stronger hot corrosion resistance, and show less segregation during solidification. Therefore, a lot of research work is focused on developing high-performance Co-based superalloys.

Among the reported cobalt-based binary systems, Co-Ti is the only known system with a thermodynamically stable L12 ordered structure γʹ-Co ₃ Ti and a disordered fcc-γ phase, and studies have shown that the strength of Co ₃ Ti exceeds that of Ni ₃ Al. In addition, Co ₃ Ti has the advantages of relatively low cost and low density. However, the large lattice mismatch between the γʹ-Co ₃ Ti phase and the fcc-γ matrix phase limits the microstructural stability and strength at high temperatures.

At present, in order to improve the toughness, high temperature resistance and ablation resistance of Co-based high-temperature alloys, some traditional ceramic particles such as Al ₂ O ₃ and Y ₂ O ₃ are used to reinforce Co-based high-temperature alloy composites. However, the addition of these ceramics easily leads to certain interface reactions, resulting in a decrease in the density of the composite material.

Using Ti ₃ AlC ₂ as a reaction precursor can cause Al dissociation reaction in the matrix at high temperature, in situ generation of TiC, which has the characteristics of high hardness and high modulus, and has better wettability with metal materials (reference: M. W. Barsoum, Prog. Solid State Chem. 28 (2000) 201-281). At present, studies have shown that when Ti ₃ AlC ₂ material is added to the Ni matrix, Al-Ti atoms will detach from Ti ₃ AlC ₂ at high temperature and react with Ni, prompting submicron Ni ₃ (Al, Ti) particles to precipitate in the Ni matrix, which will in situ generate submicron TiC and Ni ₃ (Al, Ti), achieving the effect of dual-phase synergistic strengthening of Ni-based composite materials (reference: W. Hu, Materials Science and Engineering A 697 (2017) 48-54).

However, for the Co-based high-temperature alloy matrix, this reaction and dual-phase synergistic strengthening effect cannot be easily achieved. The main reason is that the detachment of materials such as Ti ₃ AlC ₂ at high temperature is affected by temperature and elements, resulting in the detachment of Al and Ti not being equal in proportion. At the same time, since the composition range for the formation of Co ₃ (Al, Ti) dual-phase strengthening in Co-based high-temperature alloys is smaller than that of Ni-based high-temperature alloys, there is no report on Co ₃ (Al, Ti) dual-phase strengthened Co-based high-temperature alloys in the prior art.

Summary of the invention

In view of the shortcomings of the prior art, the object of the present invention is to provide a method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material. The present invention regulates the alloy components (Ti, Al) elements in the matrix so that the molten Co-Ti alloy at high temperature induces the decomposition of Ti ₃ AlC ₂ , and Al atoms and part of the Ti atoms are dissociated from the hexagonal Ti ₃ AlC ₂ interlayer structure, leaving non-stoichiometric submicron TiC particles. The Al atoms and Ti atoms further react with Co to generate a second phase Co ₃ (Al, Ti), wherein FCC_Al is a disordered phase and FCC_L12 is an ordered phase, thereby realizing the ordered-disordered synergistic strengthening effect of TiC-Co ₃ (Al, Ti).

The second object of the present invention is to provide an in-situ self-generated TiC—Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material prepared by the above preparation method.

In order to achieve the above object, the present invention adopts the following technical solution:

The present invention provides a method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material, comprising the following steps:

Step 1: Determination of matrix composition compensation

Ti ₃ AlC ₂ powder and Co powder are mixed to obtain a mixed powder, the mixed powder is pressed to obtain N green compacts, the N green compacts are sintered at different temperatures to obtain N sintered samples; then the phase composition and ingredients of the obtained sintered samples are detected to determine the reaction temperature range in which Ti ₃ AlC ₂ decomposes and forms TiC, then any temperature point is selected in the reaction temperature range to compensate the matrix composition using a phase diagram calculation method, and the mass ratio of the additionally added Ti and Al elements is calculated;

Step 2 Preparation of alloy composite materials

Ti ₃ AlC ₂ powder and Co powder are prepared in the same proportion as in step 1, and Ti powder and Al powder are prepared according to the mass ratio of the additional Ti and Al elements obtained in step 1, and then the powders are mixed to obtain composite material powder, the composite material powder is pressed into a green body, and the green body is heat-insulated and sintered at the temperature point selected in step 1 to obtain an alloy composite material;

Step 3 Heat treatment

The alloy composite material obtained in step 2 is subjected to solution treatment and aging treatment in sequence.

Since the detachment of materials such as Ti ₃ AlC ₂ at high temperature is affected by temperature and elements, the detachment of Al and Ti is not proportional. At the same time, since the composition range of Co-based high-temperature alloys to form Co ₃ (Al, Ti) dual-phase strengthening is smaller than that of Ni-based high-temperature alloys, the present invention first obtains a sintered sample by sintering Ti ₃ AlC ₂ powder and Co powder, and calculates the mass ratio of the additionally added Ti and Al elements through its composition and the Co, Al, and Ti element contents in the FCC_Al+FCC_L12 dual-phase region in the Co-Al-Ti ternary alloy phase diagram. Then, after compensating with Ti powder and Al powder, an alloy composite material is obtained by sintering. During the sintering process, a process of Ti ₃ AlC ₂ forming TiC is generated. Finally, after aging treatment, the FCC_L12 precipitation phase of Co ₃ (Al, Ti) is obtained, thereby forming a high-temperature alloy composite material with two phases synergistically reinforced by TiC particle reinforcement phase and Co ₃ (Al, Ti) precipitation reinforcement phase.

In a preferred solution, in step 1, the mass fraction of Ti ₃ AlC ₂ powder in the mixed powder is 5-25 wt.%, preferably 5-10 wt.%.

The inventors found that the mass fraction of Ti ₃ AlC ₂ powder needs to be effectively controlled. On the one hand, if there is too much Ti ₃ AlC ₂ powder, too much TiC will be decomposed in the process of composite materials, and the mechanical properties will be reduced. On the other hand, too much Ti ₃ AlC ₂ will cause too much Ti, Al to decompose, resulting in the inability to make the matrix components in the FCC_Al+FCC_L12 dual-phase region when the matrix components are compensated.

In a preferred embodiment, in step 1, the mixing method is ball milling, and the ball milling is carried out under a protective atmosphere. During the ball milling, the ball-to-material ratio is 1-5:1, and the ball milling time is 5-12 hours.

In a preferred embodiment, in step 1, the pressing pressure is 200-600 MPa, and the pressing time is 30-90 s.

In actual operation, the mixed powder is placed in Cr13 cold pressing die steel and a pressure of 200-600MPa is applied for cold pressing.

In a preferred solution, in step 1, the N green sheets are sintered at different temperatures, and water-cooled after sintering to obtain N sintered samples. The inventors found that only by using water cooling can the structure at this sintering temperature be retained, and the phase composition at the sintering temperature can be accurately measured. If furnace cooling is used, low-temperature and room-temperature structures will be generated during the cooling process, which will result in the inability to subsequently measure the phase composition of FCC_A1 at the sintering temperature.

In a preferred embodiment, in step 1, N is 5-10.

In a preferred embodiment, in step 1, the sintering process of any green sheet is to heat the temperature to the sintering holding temperature at a heating rate of 10-15°C/min and keep the temperature for 30-240min, and the sintering is carried out under a protective atmosphere.

Further preferably, the sintering and holding temperature is set in such a manner that N temperature points are selected within the range of 1000-1500°C as different sintering and holding temperatures for N compacts, and the difference between two adjacent temperature points is 50-100°C.

A preferred solution is to select a temperature point within the reaction temperature range, calculate the Co, Al, and Ti element contents of the matrix composition in the FCC_Al+FCC_L12 bidirectional zone based on the Co-Al-Ti ternary alloy phase diagram, and then calculate the mass ratio of the additionally added Ti and Al elements based on the composition of the sintered sample measured at the corresponding temperature.

In the actual operation process, a specific temperature point is taken within the reaction temperature range, and then the Co, Al, and Ti element contents of the matrix composition in the FCC_Al+FCC_L12 bidirectional zone are calculated based on the Co-Al-Ti ternary alloy phase diagram. Then, based on the composition of the sintered sample measured at the corresponding temperature, the mass ratio of the additionally added Ti and Al elements is calculated. The subsequent holding point in the sintering process is also the corresponding temperature point, because the mass ratios of Ti and Al elements that need to be compensated at different temperatures will be different.

In a preferred embodiment, in step 2, the powder mixing method is ball milling, and the ball milling is carried out under a protective atmosphere. During the ball milling, the ball-to-material ratio is 1-5:1, and the ball milling time is 5-12 hours.

Preferably, in step 2, the pressing pressure is 200-600 MPa, and the pressing time is 30-90 s.

In a preferred embodiment, in step 2, the green body is sintered by heating the green body to the reaction temperature range described in step 1 at a heating rate of 10-15°C/min and keeping the temperature for 30-240min. The sintering is performed under a protective atmosphere.

In a preferred embodiment, in step three, the temperature of the solution treatment is 1100-1300° C., the time of the solution treatment is 20-30 hours, and after the solution treatment is completed, water cooling is performed.

In a preferred embodiment, in step three, the aging treatment temperature is 600-800° C., and the aging treatment time is 50-200 h.

In the present invention, a supersaturated solid solution is obtained after solution treatment and water cooling quenching, and then L12_Co ₃ (Al, Ti) phase is precipitated through aging. However, in the present invention, the temperature of solution and aging needs to be effectively controlled. If the solution temperature is too high, on the one hand, liquid phase structure will appear, causing the alloy to melt, and on the other hand, TiC will grow. If the size of TiC is too large, the mechanical properties of the composite material will be reduced; if the solution temperature is too low, a supersaturated solid solution cannot be obtained, and harmful structures cannot be eliminated, affecting the mechanical properties; if the aging temperature is too high or too low, the volume fraction of the FCC_L12 precipitate phase may be reduced, thereby reducing the strengthening effect.

The present invention also provides an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material prepared by the above preparation method.

The TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material provided by the present invention contains submicron ceramic hard particles TiC and second phase Co ₃ (Al, Ti) particles uniformly distributed in a Co-based alloy matrix, and the reinforcing phase has good wettability with the metal matrix phase, a firm interface bond, and no microscopic defects.

Principles and advantages

The present invention first obtains a sintered sample by sintering Ti ₃ AlC ₂ powder and Co powder, and calculates the mass ratio of the additionally added Ti and Al elements according to the composition of the sintered sample and the contents of Co, Al and Ti elements in the FCC_Al+FCC_L12 dual-phase region in the Co-Al-Ti ternary alloy phase diagram. Then, after compensating with Ti powder and Al powder, an alloy composite material is obtained by sintering. During the sintering process, a process of Ti ₃ AlC ₂ forming TiC is generated. Finally, after aging treatment, an FCC_L12 precipitation phase of Co ₃ (Al, Ti) is obtained, thereby forming a high-temperature alloy composite material with two phases synergistically reinforced by a TiC particle reinforcement phase and a Co ₃ (Al, Ti) precipitation reinforcement phase.

Compared with the prior art, the present invention has at least the following advantages:

1. The present invention calculates and compensates the Co alloy matrix composition. The in-situ self-generated TiC-Co ₃ (Al, Ti) ordered and disordered synergistically reinforced high-temperature alloy composite material of the present invention can calculate different matrix alloy compensation components according to different Ti ₃ AlC ₂ addition amounts to ensure that the matrix synthesis composition is within the range that can precipitate the L12_Co ₃ (Al, Ti) phase;

Second, the in-situ self-generated TiC-Co ₃ (Al, Ti) ordered and disordered synergistically reinforced high-temperature alloy composite material of the present invention has a room temperature compressive yield strength of up to 677 MPa, which is much higher than the general ceramic-reinforced Co-based composite material;

3. The in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material of the present invention has a simple preparation process, is easy to operate, and can achieve near-net forming of materials of different shapes. It can be widely used in aerospace, military industry, machinery manufacturing, nuclear energy and other fields.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

FIG1 is a phase diagram of the Co-Al-Ti ternary system at an aging temperature of 700° C., showing the matrix composition obtained in step S15 of Example 1 of the in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material of the present invention, and the matrix composition after composition compensation in step S16 of Example 1.

FIG2 is a microstructure photograph of the in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material in Example 1 of the present invention, from which it can be clearly seen that TiC particles and diffusely distributed cubic L12 structure Co ₃ (Al, Ti) precipitated from the FCC matrix.

FIG. 3 is a stress-strain curve of the compressive properties of the in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material in Examples 1 and 2 of the present invention.

DETAILED DESCRIPTION

In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific implementation modes of the present invention are further described below.

The endpoints and any values of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, the endpoint values of each range and the individual point values, and the individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Example 1

Step S1-1, powder preparation: Ti ₃ AlC ₂ and Co-based alloy powder are prepared in the following mass ratio: Ti ₃ AlC ₂ : 5 wt.%, and the rest is Co powder;

Step S1-2, powder mixing: the ingredients in step S1-1 are placed in a vacuum ball mill with an inert atmosphere at a ball-to-material ratio of 1:1, and then the vacuum ball mill is placed on a ball mill for mixing. The mixing time is 10 hours, and then the mixed composite material powder is taken out;

Step S1-3, cold pressing: the mixed powder in step S1-2 is divided into 6 parts, and each part is cold pressed using Cr13 cold pressing die steel at a pressure of 400 MPa for 60 seconds to obtain 6 compacts;

Step S1-4, atmosphere sintering: first set 6 sintering holding temperatures, namely 1000°C, 1100°C, 1200°C, 1300°C, 400°C, and 1500°C, and put the 6 compacts obtained after cold pressing in step S1-3 into an atmosphere protection sintering furnace for sintering at the above different temperatures, with a heating rate of 10°C/min, and keep them at this temperature for 120 minutes; then take out the 6 samples obtained for water cooling;

Step S1-5, microstructure composition detection: the microstructure composition of the sintered sample in step S1-4 is measured after grinding and polishing, and the reaction temperature range for decomposing Ti ₃ AlC ₂ and forming TiC is determined to be 1100-1400°C. Within this temperature range, 1300°C is selected as the temperature point for matrix compensation calculation, and the matrix composition ratio of the Co-based alloy sintered at 1300°C is measured to be Co-Al0.955-Ti1.387;

Step S1-6, matrix component compensation calculation, according to the Co-Al-Ti ternary alloy phase diagram, the Co, Al, Ti element contents in the matrix component in the FCC_Al+FCC_L12 dual zone, as shown in FIG1, wherein the Ti element ranges from 3 to 23.4%, and the Al element ranges from 0 to 1.1 at.%, according to the matrix component ratio of the Co-based alloy sintered at 1300°C is Co-Al0.955-Ti1.387; the calculated additional added Ti element ranges from (3-1.387) to (23.4-1.387) at.%, i.e., 1.613-22.013%, and since the atomic ratio of the Al element in the matrix component of the original Co-based alloy is 0.955%, i.e., within the element range of the FCC_Al+FCC_L12 dual zone, there is no need to compensate the Al element, and it can be ensured that the matrix alloy can precipitate the L12_Co ₃ (Al, Ti) phase during the heat treatment process;

Step S1-7, secondary powder preparation: adding 10 at.% Ti powder calculated in step S1-6 to the powder in step S1-1;

Step S1-8, secondary powder mixing: the ingredients in step S1-7 are placed in a vacuum ball mill with an inert atmosphere protection at a ball-to-material ratio of 1:1, and then the vacuum ball mill is placed on a ball mill for mixing. The mixing time is 10 hours, and then the mixed composite material powder is taken out;

Step S1-9, secondary atmosphere sintering: the cold-pressed embryo in step S1-8 is placed in an atmosphere protection sintering furnace for sintering, the temperature is raised to 1300°C at a heating rate of 10°C/min, and the temperature is kept at this temperature for 120 minutes; then the sample is taken out after cooling to room temperature in the furnace;

Step S1-10, heat treatment: the sample obtained in step S1-9 is subjected to solution treatment and aging treatment, the solution temperature is 1100°C, the solution time is 20 hours, and water cooling is performed to obtain a supersaturated solid solution; the aging temperature is 700°C, and the aging time is 100 hours; the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material is obtained.

Step S1-11, processing the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material obtained in step S1-10 into a cylindrical compression specimen with a diameter of 4 mm and a height of 6 mm, and performing a compression test on a mechanical testing machine at a rate of 1 mm/min; the room temperature compressive yield strength thereof is measured to be 629 MPa.

Example 2

Step D1-1, microstructure composition detection: the previous steps are the same as those in Example 1, except that 1400°C is selected as the temperature point for matrix compensation calculation. The matrix composition mass ratio of the Co-based alloy sintered at 1400°C is measured to be Co-Al1.032-Ti1.413;

Step D1-2, matrix composition compensation calculation, according to the matrix composition Co-Al1.032-Ti1.413 of the Co-based alloy obtained in step D1-1, the matrix composition is compensated using the phase diagram calculation method, and the atomic ratio of the additionally added Ti and Al elements is calculated: Ti element (3-1.413)-(23.4-1.413) at.%, that is, 1.587-21.987%, without the need to compensate the Al element, which can ensure that the matrix alloy can precipitate L12_Co ₃ (Al, Ti) phase during the heat treatment process;

Step D1-3, secondary powder preparation: adding 15 wt.% Ti powder calculated in step D1-2 to the powder in step S11;

Step D1-4, secondary powder mixing: the ingredients in step D1-3 are placed in a vacuum ball mill with an inert atmosphere protection at a ball-to-material ratio of 1:1, and then the vacuum ball mill is placed on a ball mill for mixing. The mixing time is 10 hours, and then the mixed composite material powder is taken out;

Step D1-5, secondary atmosphere sintering: the cold-pressed embryo in step D1-4 is placed in an atmosphere protection sintering furnace for sintering, the temperature is raised to 1400°C at a heating rate of 10°C/min, and the temperature is kept at this temperature for 120 minutes; then the sample is taken out after cooling to room temperature in the furnace;

Step D1-6, heat treatment: the sample obtained in step D1-5 is subjected to solution treatment and aging treatment, the solution temperature is 1100°C, the solution time is 20h, and water cooling is performed to obtain a supersaturated solid solution; the aging temperature is 700°C, and the aging time is 100h; the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material is obtained.

Step D1-7, processing the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material obtained in step D1-6 into a cylindrical compression specimen with a diameter of 4 mm and a height of 6 mm, and performing a compression test on a mechanical testing machine at a rate of 1 mm/min; the room temperature compressive yield strength thereof is measured to be 677 MPa.

Example 3

Step S2-1, powder preparation: Ti ₃ AlC ₂ and Co-based alloy powder are prepared in the following mass ratio: Ti ₃ AlC ₂ : 10 wt.%, and the rest is Co powder;

Step S2-2, powder mixing: the ingredients in step S2-1 are placed in a vacuum ball mill with an inert atmosphere at a ball-to-material ratio of 1:1, and then the vacuum ball mill is placed on a ball mill for mixing. The mixing time is 10 hours, and then the mixed composite material powder is taken out;

Step S2-3, cold pressing: the mixed powder in step S2-2 is divided into 6 parts, and each part is cold pressed using Cr13 cold pressing die steel at a pressure of 400 MPa for 60 seconds to obtain 6 compacts;

Step S2-4, atmosphere sintering: first set 6 sintering holding temperatures, namely 1000°C, 1100°C, 1200°C, 1300°C, 1400°C, and 1500°C, and put the 6 compacts obtained after cold pressing in step S2-3 into an atmosphere protection sintering furnace for sintering at the above different temperatures, with a heating rate of 10°C/min, and keep them at this temperature for 120 minutes; then take out the 6 samples obtained for water cooling;

Step S2-5, microstructure composition detection: the microstructure composition of the sintered sample in step S2-4 is measured after grinding and polishing, and the reaction temperature range for decomposing Ti ₃ AlC ₂ and forming TiC is determined to be 1100-1400°C. Within this temperature range, 1300°C is selected as the temperature point for matrix compensation calculation, and the matrix composition ratio of the Co-based alloy sintered at 1300°C is measured to be Co-Al1.0-Ti2.8;

Step S2-6, matrix component compensation calculation, according to the Co-Al-Ti ternary alloy phase diagram, the Co, Al, Ti element contents in the matrix component in the FCC_Al+FCC_L12 dual zone, as shown in FIG1, wherein the Ti element ranges from 3 to 23.4%, and the Al element ranges from 0 to 1.1 at.%, according to the matrix component ratio of the Co-based alloy sintered at 1300°C being Co-Al1.0-Ti2.8; the calculated range of the additionally added Ti element is (3-2.8)-(23.4-2.8) at.%, i.e., 0.2-20.6%, and since the atomic ratio of the Al element in the matrix component of the original Co-based alloy is 1.0%, i.e., within the element range of the FCC_Al+FCC_L12 dual zone, there is no need to compensate the Al element, and it can be ensured that the matrix alloy can precipitate the L12_Co3 (Al, Ti) phase during the heat treatment process;

Step S2-7, secondary powder preparation: adding 15 at.% Ti powder calculated in step S2-6 to the powder in step S2-1;

Step S2-8, secondary powder mixing: the ingredients in step S2-7 are placed in a vacuum ball mill with an inert atmosphere at a ball-to-material ratio of 1:1, and then the vacuum ball mill is placed on a ball mill for mixing. The mixing time is 10 hours, and then the mixed composite material powder is taken out;

Step S2-9, secondary atmosphere sintering: the cold-pressed embryo in step S2-8 is placed in an atmosphere protection sintering furnace for sintering, the temperature is raised to 1300°C at a heating rate of 10°C/min, and the temperature is kept at this temperature for 120 minutes; then the sample is taken out after cooling to room temperature in the furnace;

Step S2-10, heat treatment: the sample obtained in step S2-9 is subjected to solution treatment and aging treatment, the solution temperature is 1100°C, the solution time is 20 hours, and water cooling is performed to obtain a supersaturated solid solution; the aging temperature is 700°C, and the aging time is 100 hours; the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material is obtained.

Step S2-11, the final in-situ self-generated TiC-Co3 (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material obtained in step S2-10 is processed into a cylindrical compression specimen with a diameter of 4 mm and a height of 6 mm, and a compression test is performed on a mechanical testing machine at a rate of 1 mm/min; the room temperature compressive yield strength is measured to be 692 MPa.

Example 4

Step D2-1, microstructure composition detection: the previous steps are the same as those in Example 2, except that 1200°C is selected as the temperature point for matrix compensation calculation. The matrix composition mass ratio of the Co-based alloy sintered at 1200°C is measured to be Co-Al0.99-Ti2.76;

Step D2-2, matrix composition compensation calculation, according to the matrix composition Co-Al0.99-Ti2.76 of the Co-based alloy obtained in step S15, the matrix composition is compensated using the phase diagram calculation method, and the atomic ratio of the additionally added Ti and Al elements is calculated: Ti element (3-2.76)-(23.4-2.76) at.%, and there is no need to compensate the Al element, which can ensure that the matrix alloy can precipitate L12_Co ₃ (Al, Ti) phase during the heat treatment process;

Step D2-3, secondary powder preparation: adding 15 wt.% Ti powder calculated in step D2-2 to the powder in step S2-1;

Step D2-4, secondary powder mixing: the ingredients in step D2-3 are placed in a vacuum ball mill with an inert atmosphere protection at a ball-to-material ratio of 1:1, and then the vacuum ball mill is placed on a ball mill for mixing. The mixing time is 10 hours, and then the mixed composite material powder is taken out;

Step D2-5, secondary atmosphere sintering: the cold-pressed embryo in step D2-4 is placed in an atmosphere protection sintering furnace for sintering, the temperature is raised to 1200°C at a heating rate of 10°C/min, and the temperature is kept at this temperature for 120 minutes; then the sample is taken out after cooling to room temperature in the furnace;

Step D2-6, heat treatment: the sample obtained in step D2-5 is subjected to solution treatment and aging treatment, the solution temperature is 1100°C, the solution time is 20h, and water cooling is performed to obtain a supersaturated solid solution; the aging temperature is 700°C, and the aging time is 100h; the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material is obtained.

Step D2-7, processing the final in-situ self-generated TiC-Co ₃ (Al, Ti) ordered-disordered synergistically reinforced high-temperature alloy composite material obtained in step D2-6 into a cylindrical compression specimen with a diameter of 4 mm and a height of 6 mm, and performing a compression test on a mechanical testing machine at a rate of 1 mm/min; the room temperature compressive yield strength thereof is measured to be 642 MPa.

Comparative Example 1

The remaining steps are the same as those in Example 1, except that Ti ₃ AlC ₂ and Co-based alloy powders are prepared in the following mass ratio: Ti ₃ AlC ₂ : 30 wt.%, and the rest is Co powder;

When sintering at 6 temperatures (1000℃, 1100℃, 1200℃, 1300℃, 1400℃, 1500℃), it was found that the samples all melted. Alloys with too low melting points are not suitable for making high-temperature alloys.

Comparative Example 2

The remaining steps are the same as those in Example 1, except that in step S1-4, the 6 samples taken out for water cooling are replaced with furnace cooling; at this time, room temperature structure appears during the cooling process, which makes it impossible to measure the Al and Ti element contents dissolved in the matrix, and to perform subsequent matrix composition compensation calculations.

The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations made to these embodiments without departing from the principles and spirit of the present invention are still within the protection scope of the present invention.

Claims (10)

1. A method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material, characterized in that it comprises the following steps: Step 1: Determination of matrix composition compensation Ti ₃ AlC ₂ powder and Co powder are mixed to obtain a mixed powder, the mixed powder is pressed to obtain N green compacts, the N green compacts are sintered at different temperatures to obtain N sintered samples; then the phase composition and ingredients of the obtained sintered samples are detected to determine the reaction temperature range in which Ti ₃ AlC ₂ decomposes and forms TiC, then any temperature point is selected in the reaction temperature range to compensate the matrix composition using a phase diagram calculation method, and the mass ratio of the additionally added Ti and Al elements is calculated; Step 2 Preparation of alloy composite materials Ti ₃ AlC ₂ powder and Co powder are prepared in the same proportion as in step 1, and Ti powder and Al powder are prepared according to the mass ratio of the additional Ti and Al elements obtained in step 1, and then the powders are mixed to obtain composite material powder, the composite material powder is pressed into a green body, and the green body is heat-insulated and sintered at the temperature point selected in step 1 to obtain an alloy composite material; Step 3 Heat treatment The alloy composite material obtained in step 2 is subjected to solution treatment and aging treatment in sequence. 2. The method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: in step 1, the mass fraction of Ti ₃ AlC ₂ powder in the mixed powder is 5-25 wt.%. 3. The method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: in step 1, the mixing method is ball milling, the ball milling is carried out under a protective atmosphere, the ball-to-material ratio is 1-5:1, and the ball milling time is 5-12h; In step 1, the pressing pressure is 200-600 MPa, and the pressing time is 30-90 s. 4. The method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: in step 1, the N pressed green sheets are sintered at different temperatures respectively, and water-cooled after sintering to obtain N sintered samples; In step 1, N is 5-10; In step 1, the sintering process of any green sheet is to heat the green sheet to the sintering holding temperature at a heating rate of 10-15°C/min and keep the temperature for 30-240min. The sintering is carried out under a protective atmosphere. 5. A method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 4, characterized in that: the sintering and heat preservation temperature is set in a manner of: taking N temperature points in the range of 1000-1500°C as different sintering and heat preservation temperatures for N compacts, and the difference between two adjacent temperature points is 50-100°C. 6. A method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: a temperature point is selected within the reaction temperature range, and the Co, Al, and Ti element contents of the matrix composition in the FCC_Al+FCC_L12 bidirectional region are calculated according to the Co-Al-Ti ternary alloy phase diagram, and then the mass ratio of the additionally added Ti and Al elements is calculated according to the composition of the sintered sample measured at the corresponding temperature. 7. The method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: in step 2, the powder mixing method is ball milling, the ball milling is carried out under a protective atmosphere, the ball-to-material ratio is 1-5:1, and the ball milling time is 5-12h; In step 2, the pressing pressure is 200-600 MPa, and the pressing time is 30-90 s. 8. The method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: in step 2, the process of sintering the green body is: heating the temperature to the reaction temperature range of step 1 at a heating rate of 10-15°C/min, and keeping the temperature for 30-240min, and the sintering is carried out under a protective atmosphere. 9. The method for preparing an in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material according to claim 1, characterized in that: in step 3, the temperature of the solid solution treatment is 1100-1300°C, the time of the solid solution treatment is 20-30h, and after the solid solution treatment is completed, water cooling is performed; In step three, the aging treatment temperature is 600-800°C, and the aging treatment time is 50-200h. 10. An in-situ self-generated TiC-Co ₃ (Al, Ti) synergistically reinforced high-temperature alloy composite material prepared by the preparation method according to any one of claims 1 to 9.