Regulation and control method for residual stress in aluminum-based composite material

Abstract

The invention provides a method for regulating and controlling residual stress in an aluminum-based composite material, which relates to the field of metal-based composite materials, and comprises the following steps: sequentially carrying out annealing treatment, subzero treatment and cold and hot cycle treatment on an aluminum-based composite material blank to form reticular dislocation in the aluminum-based composite material, and the microcosmic residual stress in the aluminum-based composite material is reduced to 25 MPa or below. According to the method, macroscopic residual stress in the material is eliminated through annealing treatment, then microcosmic residual stress is reduced through subzero treatment, the stress is relieved, macroscopic stress cannot be generated again in follow-up treatment, finally, thermocycling heat treatment under the simulated service environment is carried out, base position dislocation configuration in the material is adjusted, and the thermal performance of the material is improved. Low-energy net dislocation is generated, microstress is reduced as far as possible, and the situation that the size precision and the surface roughness of a precise instrument are affected due to accumulative deformation generated by repeated stress release of materials in a service environment is avoided, so that the device adapts to an air-space cold-heat alternating service environment.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal matrix composites, and particularly relates to a residual stress regulation method for an aluminum matrix composite. BACKGROUND

[0002] The aluminum matrix composite has characteristics such as high modulus and low thermal expansion coefficient, and has small size change under stress and heat, and is a key structure-function integrated material in fields such as space remote sensing and space exploration. With the rapid advancement of China's satellite networking and deep space strategic missions, the requirements for aluminum matrix composites with high size stability and high surface precision are increasingly demanding.

[0003] Residual stress is an important factor affecting the size stability and surface precision of materials. Due to the large difference in the thermal expansion coefficients of the reinforcing body and the matrix, the aluminum matrix composite produces not only macro residual stress after preparation and processing, but also significant micro residual stress.

[0004] At present, the methods for removing the residual stress of the aluminum matrix composite are mainly heat treatment stress relief. Different temperature holding and cooling are performed on different workpieces to remove the macro residual stress. Among them, annealing and deep cooling are the most typical two stress relief methods, but these two methods cannot completely eliminate the macro and micro residual stress, and therefore cannot completely meet the requirements of high size stability parts for aerospace use. SUMMARY

[0005] Therefore, the application provides a residual stress regulation method for an aluminum matrix composite, which can solve the problem that the residual stress in the aluminum matrix composite is difficult to effectively reduce in the prior art, thereby making the aluminum matrix composite unsuitable for use in the aerospace field.

[0006] To solve the above problems, the application provides a residual stress regulation method for an aluminum matrix composite, which comprises the following steps:

[0007] Step 1): annealing the aluminum matrix composite blank to eliminate the macro residual stress of the aluminum matrix composite blank and obtain an annealed blank;

[0008] Step 2): deep cooling the annealed blank to eliminate more than 50% of the micro residual stress in the annealed blank and obtain a deep-cooled blank;

[0009] Step 3): cold and hot cycle treatment of the deep-cooled blank to form a network of dislocations in the aluminum matrix composite and reduce the micro residual stress in the aluminum matrix composite to less than 25 MPa;

[0010] The cold and hot cycle treatment adopts a simulated service environment temperature.

[0011] Further, in the step 1), the temperature of the annealing treatment is 350-480℃; the time of the annealing treatment is 1-48h.

[0012] Further, in the step 2), the temperature of the cryogenic treatment is -252℃ to -150℃; and / or

[0013] The cooling rate of the cryogenic treatment is greater than 10℃ / min.

[0014] Further, the cold-heat cycle treatment comprises sequentially performing a first temperature rising treatment, a temperature falling treatment and a second temperature rising treatment.

[0015] Preferably, the cycle number is 1-6.

[0016] Further, the step of sequentially performing a first temperature rising treatment, a temperature falling treatment and a second temperature rising treatment specifically comprises:

[0017] warming the blank after the cryogenic treatment from room temperature to a first set temperature, then cooling to a second set temperature, and then warming to room temperature;

[0018] Preferably, the first set temperature is the highest temperature of the service environment ±5℃; and the second set temperature is the lowest temperature of the service environment ±5℃.

[0019] Preferably, the temperature rising rate and the temperature falling rate are the same.

[0020] Further, in the step 1), the reinforcing body in the aluminum matrix composite blank is SiC micron ceramic particles and / or B4C micron ceramic particles; and / or

[0021] The volume content of the reinforcing body in the aluminum matrix composite blank is 10%-75%; and / or

[0022] The matrix in the aluminum matrix composite blank is one of 1-series aluminum alloy-7-series aluminum alloy.

[0023] Further, the maximum size of the aluminum matrix composite blank is L;

[0024] When L≤100mm, the time t of the cryogenic treatment is 30+5×lnL;

[0025] When L>100mm, the time t of the cryogenic treatment is 30+12×lnL.

[0026] Further, the surface roughness change value ΔRZ of the aluminum matrix composite after the residual stress regulation before and after service is less than 0.01μm.

[0027] The application provides a method for regulating residual stress in an aluminum matrix composite material.

[0028] The method for regulating residual stress in the aluminum matrix composite material comprises the following steps: annealing an aluminum matrix composite material blank to eliminate macro residual stress in the aluminum matrix composite material blank and obtain an annealed blank; deep cooling the annealed blank to eliminate more than 50% of micro residual stress in the annealed blank and obtain a deep-cooled blank; and performing cold-heat cycle treatment on the deep-cooled blank to obtain the aluminum matrix composite material; wherein the cold-heat cycle treatment adopts a simulated service environment temperature. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. The drawings in the following description are only exemplary, and for those skilled in the art, other drawings can be derived from the provided drawings without creative labor.

[0030] Figure 1 is a stress test result graph of different forms of samples in the embodiment 1 of the application; wherein (a) is macro stress; (b) is micro stress in the aluminum matrix; (c) is micro stress in the reinforcing body;

[0031] Figure 2 is a microstructure graph of the aluminum matrix composite material in the embodiment 1 of the application. DETAILED DESCRIPTION

[0032] To further clarify the technical means and effects taken by the present application to achieve the intended purpose, the following describes the specific embodiments, structures, features and effects according to the present application in detail with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "embodiments" do not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0033] In the existing stress reduction method of particle reinforced composite materials, high and low temperature treatment is used, but this method only uses high and low temperature treatment, and in the case where different types of stress are not eliminated, new stress is introduced, leading to mutual influence of residual stress from multiple sources, and the stress state is difficult to reach a metastable low stress state suitable for space and time cold and hot alternating service environment. In the method of the present application, annealing, deep cooling and near-service environment cold and hot cycle treatment process are combined to reduce and control residual stress. The treatment method and parameters are easier to determine, and the adjusted stress state is more suitable for the stress requirements in the service environment. At the same time, it can adapt to different service environments, and can also achieve reasonable residual stress reduction for different sizes of parts. The specific scheme is as follows:

[0034] The present application provides a method for controlling residual stress in aluminum matrix composites, comprising the following steps:

[0035] Step 1): annealing the aluminum matrix composite blank at 350-480℃ to eliminate the macro residual stress of the aluminum matrix composite blank, and obtaining the annealed blank;

[0036] The aluminum matrix composite blank is a plate, rod or block obtained by simple machining, or a workpiece blank with a certain machining allowance after rough machining; the annealing time is selected between 1-48h according to the size of the blank, and the larger the size, the longer the annealing time; the cooling method after annealing is furnace cooling;

[0037] The reinforcing body in the aluminum matrix composite blank is SiC micron ceramic particles and / or B4C micron ceramic particles; the volume content of the reinforcing body is 10%-75%; the matrix in the aluminum matrix composite blank is one of 1-series aluminum alloy-7-series aluminum alloy.

[0038] Step 2): deep cooling the annealed blank at -252℃ to -150℃ to eliminate more than 50% of the micro residual stress in the annealed blank, and obtaining the deep cooled blank;

[0039] The deep cryogenic treatment is selected to be performed in an environment not higher than -150℃, and the lowest temperature can be selected to be -252℃ (liquid hydrogen temperature) to ensure the temperature difference of deep cryogenic treatment. The deep cryogenic treatment is performed 1-3 times, preferably 1 time. The maximum size of the aluminum-based composite material blank is L. When L≤100mm, the time t of deep cryogenic treatment is 30+5×lnL. When L>100mm, the time t of deep cryogenic treatment is 30+12×lnL. The deep cryogenic cooling rate needs to be greater than 10℃ / min. The deep cryogenic heating time is 1.5-3 times of the deep cryogenic holding time. The larger the size, the slower the heating. The above formula ensures that the core of the blank is cooled through.

[0040] Step 3): The blank after deep cryogenic treatment is subjected to cold-heat cycle treatment to obtain an aluminum-based composite material, and low-energy net dislocations are formed in the aluminum-based composite material, and the micro residual stress in the aluminum-based composite material is reduced to below 25MPa without introducing macro residual stress. The cold-heat cycle treatment adopts a simulated service environment temperature.

[0041] This step is specifically: the blank after deep cryogenic treatment is heated from room temperature to a first set temperature (service environment maximum temperature±5℃), then cooled to a second set temperature (service environment minimum temperature±5℃), then heated to room temperature, and cycled 1-6 times, preferably 3 times. The time of one cycle is 24h, and the heating rate and the cooling rate are the same.

[0042] The above cold-heat cycle treatment adopts an artificial device to simulate the cold-heat temperature change of the space service environment. The artificial device can manufacture a constant temperature change rate of the service environment without holding in between. The single temperature cycle time can be controlled in the range of 0.5-100h. The device is an equipment with the ability to simulate different service environment temperature changes. After setting the service environment temperature change, the internal temperature uniformity is good, and the deviation from the set temperature is within ±5℃. The internal volume can meet the placement of aluminum-based composite material blanks of various sizes.

[0043] It should be noted that, based on the above method, the macro residual stress in the material is first eliminated by annealing treatment, on the one hand, to avoid deformation or cracking due to stress concentration in subsequent treatment, and on the other hand, annealing can reduce the interface stress between the matrix and the reinforcing phase, providing a uniform micro foundation for subsequent cryogenic treatment; then the micro residual stress is reduced by cryogenic treatment, so that the stress is relieved, and macro stress will not be generated again in the subsequent cold and hot cycle treatment; finally, the cold and hot cycle heat treatment in the simulated service environment is carried out, the dislocation configuration of the aluminum matrix composite is adjusted, the low-energy network dislocation is generated, and the micro stress is reduced as much as possible, so that the cumulative deformation of the material due to repeated stress release in the service environment is avoided, the size accuracy and surface roughness of the precision instrument are affected, so that the metastable low stress suitable for space and time cold and hot alternating service environment is obtained, which is suitable for long-term cold and hot service working condition, and has wide application prospect in the field of aerospace.

[0044] wherein "the maximum dimension L" is the longest linear dimension of the geometric shape of the aluminum matrix composite blank.

[0045] The macro residual stress refers to the stress remaining in the material after the external load or thermal gradient is removed, which is uniformly distributed on multiple grains and balanced in the entire material body; the micro residual stress refers to the stress change between grains or different phases, which is usually caused by the difference in grain orientation, phase property or anisotropy, and is balanced on multiple grains. The network dislocation refers to the complex three-dimensional structure formed by the interaction, intersection and entanglement of dislocations, which usually shows as planar dislocation boundaries, which separate the material into multiple almost dislocation-free sub-grains or regions. The formation of network dislocation is beneficial to reduce the residual stress in the material.

[0046] The present application is further illustrated below in conjunction with specific examples and comparative examples.

[0047] Example 1

[0048] The present embodiment provides a method for regulating residual stress in an aluminum matrix composite, comprising the following steps:

[0049] Step 1): annealing treatment of the aluminum matrix composite blank at 430℃ for 24h to eliminate the macro residual stress of the aluminum matrix composite blank, and obtain the blank after annealing treatment;

[0050] wherein the aluminum matrix composite blank is a cylindrical sample machined from the core of an initial 40vol.%SiC / 6061Al composite blank ingot ;

[0051] Step 2): Immerse the annealed blank in liquid nitrogen for cryogenic treatment. Specifically, hold at liquid nitrogen temperature (-196℃) for 45 minutes, then raise the temperature to room temperature over 90 minutes to obtain the cryogenically treated blank.

[0052] Step 3): The cryogenically treated blank is heated from room temperature to 127°C, then cooled to -183°C, and then heated back to room temperature. This cycle is repeated 4 times to obtain the aluminum-based composite material. The time of one cycle is 24 hours, and the heating rate and cooling rate are the same.

[0053] The residual stress at the core location of cylindrical samples in different states was measured using neutron diffraction, such as... Figure 1 As shown, the macroscopic residual stress of the initial sample is basically zero, but the microscopic residual stress of the aluminum phase (matrix) is about 110 MPa, and the microscopic residual stress of the silicon carbide phase (reinforcement) is about -190 MPa, indicating relatively high microscopic residual stress. After annealing-cryogenic treatment, the microscopic residual stress of the aluminum phase decreased to about 40 MPa, and the microscopic residual stress of the silicon carbide phase decreased to about -90 MPa, but it was not completely eliminated. After near-service process thermal cycling treatment, the triaxial (where ND, RD, and TD represent the axial stress, radial stress, and tangential stress of the cylindrical sample, respectively) microscopic residual stress was basically eliminated, reaching about 0 MPa, and no macroscopic residual stress was introduced. Observing the microstructure of the sample (aluminum matrix composite) after near-service process thermal cycling treatment, as shown... Figure 2 As shown, network dislocations can be clearly observed.

[0054] The cylindrical sample of aluminum-based composite material obtained in this embodiment was further processed into... The rod-shaped samples were subjected to cold and hot service environment exposure tests according to the service environment exposure test standard of GB / T 2423.22-2012. The test results showed that the maximum dimensional deviation of the straightness of its axis was only 10 μm, indicating that the aluminum matrix composite material obtained by the method of this embodiment has excellent dimensional stability.

[0055] Example 2

[0056] This embodiment provides a method for controlling residual stress in aluminum-based composite materials, including the following steps:

[0057] Step 1): Anneal the aluminum matrix composite blank at 400℃ for 20 hours to eliminate the macroscopic residual stress of the aluminum matrix composite blank and obtain the annealed blank.

[0058] Among them, the aluminum-based composite material blank is machined from the core of an initial 60 vol.% SiC / 6061Al composite material blank. Cylindrical sample;

[0059] Step 2): deep cryogenic treatment of the annealed blank at -160℃ for 45 min, followed by a 90 min temperature rise to room temperature, and obtaining the deep cryogenic treated blank;

[0060] Step 3): temperature rise from room temperature to 35℃, then temperature drop to -98℃, then temperature rise to room temperature, and cycling 2 times, obtaining the aluminum matrix composite; wherein, the time of one cycle is 48h, and the temperature rise rate and the temperature drop rate are the same.

[0061] The cold-heat cycle treatment in the above step 3) is to simulate the service environment on the surface of Mars. According to the publicly disclosed measurement of the minimum temperature of Mars after landing, the maximum temperature of Mars atmosphere is 35℃, and the minimum temperature is -98℃.

[0062] The residual stress of the core of the aluminum matrix composite obtained in this embodiment is measured. After the near-service process cold-heat cycle treatment, the macro residual stress is also eliminated, the micro residual stress is basically eliminated, close to 0MPa, and no macro residual stress is introduced. The aluminum matrix composite sample obtained in this embodiment is further processed into a φ120x30mm 3 round pie-shaped sample, and one side surface is processed, polished and the like to obtain a surface roughness RZ<0.05μm. Subsequently, the cold-heat service environment exposure test is carried out according to the service environment exposure test standard of GB / T2423.22-2012. The results show that the surface roughness change value ΔRZ<0.01μm before and after the cold-heat service, and the surface precision stability is excellent.

[0063] Comparative Example 1

[0064] This comparative example provides a method for regulating residual stress in an aluminum matrix composite, comprising the following steps: annealing the aluminum matrix composite blank at 430℃, the annealing cooling time is 24h, and obtaining the aluminum matrix composite;

[0065] Wherein, the aluminum matrix composite blank is a cylindrical sample machined from the core of an initial 40vol.%SiC / 6061Al composite material blank ingot .

[0066] The residual stress of the sample obtained after the above annealing treatment is measured, and it is found that the macro residual stress is basically eliminated, the micro residual stress is uniformly distributed, the aluminum phase micro residual stress is 120MPa, and the silicon carbide phase micro residual stress is about -200MPa. This shows that annealing can only remove macro residual stress, but micro residual stress still exists, and the value is large. The material subjected to the above treatment is processed into The cold and hot service environment exposure test was carried out on the rod-shaped sample according to the service environment exposure test standard of GB / T 2423.22-2012, and the test result showed that the maximum size deviation of the straightness of the axis was 50 μm, and the dimensional stability was not as good as that of the sample obtained in Example 1.

[0067] Comparative Example 2

[0068] The present comparative example provides a method for regulating residual stress in an aluminum matrix composite material, comprising the following steps:

[0069] Step 1): annealing the aluminum matrix composite material blank at 430℃ for 24h to eliminate the macro residual stress of the aluminum matrix composite material blank, and obtaining the annealed blank;

[0070] The aluminum matrix composite material blank is a cylindrical sample machined from the core of a 40vol.%SiC / 6061Al composite material blank ingot in the initial state.

[0071] Step 2): immersing the annealed blank into liquid nitrogen for cryogenic treatment, specifically, keeping at liquid nitrogen temperature (-196℃) for 45min, and then heating to room temperature for 90min, and obtaining the aluminum matrix composite material.

[0072] The residual stress test was carried out on the sample after cryogenic treatment of the present comparative example, and it was found that the macro residual stress was basically eliminated, and the micro residual stress was reduced to within 50MPa. And under the service environment, the stress state after service was compared, although the macro and micro residual stress levels were low, but the stress state was completely different from that after service. The initial state is not suitable for the environment; and the cold and hot service environment exposure test was carried out according to the process of Example 1. The test result showed that the maximum size deviation of the straightness of the axis was 20 μm, and the dimensional stability was not as good as that of the sample of Example 1.

[0073] Comparative Example 3

[0074] The present comparative example provides a method for regulating residual stress in an aluminum matrix composite material, comprising the following steps:

[0075] aging the aluminum matrix composite material blank at 200℃ for 6h to eliminate the macro residual stress of the aluminum matrix composite material blank, and obtaining the aluminum matrix composite material;

[0076] The residual stress measurement was carried out on the sample obtained after the above aging treatment, and it was found that the macro residual stress was 110MPa, the aluminum phase micro residual stress was about 150MPa, and the silicon carbide phase micro residual stress was about -50MPa, i.e. the macro and micro residual stresses were not eliminated. The sample after aging was further processed into ​The sample was a disc-shaped sample, and one side of the surface was processed and polished to obtain a surface roughness RZ < 0.05 μm. Then, the cold and hot service environment exposure test was carried out according to the service environment exposure test standard GB / T 2423.22-2012. The results showed that the surface roughness change value ΔRZ > 0.07 μm before and after cold and hot service, that is, the dimensional stability was poor.

[0077] Comparative Example 4

[0078] This comparative example provides a method for controlling residual stress in aluminum-based composite materials, including the following steps:

[0079] Step 1): Anneal the aluminum matrix composite blank at 380℃ for 16 hours to eliminate the macroscopic residual stress of the aluminum matrix composite blank and obtain the annealed blank.

[0080] Among them, the aluminum-based composite material blank is machined from the core of an initial 60 vol.% SiC / 6061Al composite material blank. Cylindrical sample;

[0081] Step 2): The annealed blank is cryogenically treated at -160℃ for 45 minutes, and then heated to room temperature for 90 minutes to obtain the cryogenically treated blank.

[0082] Residual stress tests were performed on the samples after cryogenic treatment in this comparative example. The results showed that the macroscopic residual stress was eliminated after the near-service process thermal cycling treatment, the microscopic residual stress was reduced to less than 50 MPa, and no macroscopic residual stress was introduced.

[0083] The annealed and cryogenically cooled samples are further processed into A disc-shaped sample was prepared, and one side of the sample was processed and polished to obtain a surface roughness RZ < 0.05 μm. Subsequently, a cold and hot service environment exposure test was conducted according to the service environment exposure test standard GB / T2423.22-2012. The results showed that the surface roughness change value ΔRZ > 0.03 μm before and after cold and hot service, indicating poor dimensional stability.

[0084] Comparative Example 5

[0085] This comparative example provides a method for controlling residual stress in aluminum-based composite materials, including the following steps:

[0086] Step 1): Anneal the aluminum matrix composite blank at 430℃ for 24 hours to eliminate the macroscopic residual stress of the aluminum matrix composite blank and obtain the annealed blank.

[0087] The cylindrical sample is machined from the core of a 40vol.% SiC / 6061Al composite billet in an initial state ;

[0088] Step 2): the billet after annealing is heated from room temperature to 127℃, then cooled to -183℃, then heated to room temperature, and cycled 4 times to obtain an aluminum-based composite material; wherein the time of one cycle is 24h, and the heating rate and the cooling rate are the same.

[0089] The residual stress of the sample obtained after the above cold and hot cycle treatment is measured, and it is found that the macro residual stress at the center position is basically eliminated, the micro residual stress is uniformly distributed, the aluminum phase micro residual stress is about 80MPa, and the silicon carbide phase micro residual stress is about -115MPa. This shows that annealing can only remove macro residual stress, but micro residual stress still exists and the value is large. The material subjected to the above treatment is processed into rod-shaped sample, and cold and hot service environment exposure test is carried out according to the service environment exposure test standard of GB / T 2423.22-2012. The test results show that the maximum size deviation of the straightness of the axis is 30μm, and the dimensional stability is not as good as the sample obtained in Example 1.

[0090] Comparative Example 6

[0091] This comparative example provides a method for regulating residual stress in an aluminum-based composite material, comprising the following steps:

[0092] Step 1): immerse the aluminum-based composite material billet in liquid nitrogen for cryogenic treatment, specifically, heat preservation at liquid nitrogen temperature (-196℃) for 45min, then heat to room temperature in 90min, and obtain the billet after cryogenic treatment;

[0093] The cylindrical sample is machined from the core of a 40vol.% SiC / 6061Al composite billet in an initial state ;

[0094] Step 2): the billet after cryogenic treatment is heated from room temperature to 127℃, then cooled to -183℃, then heated to room temperature, and cycled 4 times to obtain an aluminum-based composite material; wherein the time of one cycle is 24h, and the heating rate and the cooling rate are the same.

[0095] The residual stress of the sample obtained after the above cold and hot cycle treatment is measured, and it is found that the macro residual stress at the center position is basically eliminated, the micro residual stress is uniformly distributed, the aluminum phase micro residual stress is about 80MPa, and the silicon carbide phase micro residual stress is about -115MPa. This shows that annealing can only remove macro residual stress, but micro residual stress still exists and the value is large. The material subjected to the above treatment is processed into The rod-shaped sample of the application was subjected to cold and hot service environment exposure test according to GB / T 2423.22-2012 service environment exposure test standard. The test result shows that the maximum size deviation of the straightness of the axis is 75 μm, and the dimensional stability is not as good as that of the sample obtained in Example 1.

[0096] Those skilled in the art can easily understand that the advantageous technical features of the above-mentioned modes can be freely combined and superimposed without conflict.

[0097] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for controlling residual stress in aluminum-based composite materials, characterized in that, Includes the following steps: Step 1): Anneal the aluminum-based composite material blank to eliminate the macroscopic residual stress of the aluminum-based composite material blank and obtain the annealed blank. Step 2): Perform cryogenic treatment on the annealed blank to eliminate more than 50% of the micro residual stress in the annealed blank and obtain the cryogenically treated blank. Step 3): The cryogenically treated blank is subjected to a hot and cold cycle treatment to form a network of dislocations in the aluminum matrix composite material and reduce the micro residual stress in the aluminum matrix composite material to below 25 MPa. The hot and cold cycling process uses simulated service environment temperatures.

2. The method for controlling residual stress in aluminum-based composite materials according to claim 1, characterized in that, In step 1), the annealing temperature is 350–480°C, and the annealing time is 1–48 h.

3. The method for controlling residual stress in aluminum-based composite materials according to claim 1, characterized in that, In step 2), the temperature of the cryogenic treatment is -252℃ to -150℃; and / or The cooling rate of the cryogenic treatment is greater than 10℃ / min.

4. The method for controlling residual stress in aluminum-based composite materials according to claim 1, characterized in that, The hot and cold cycle process includes: sequentially performing a first heating process, a cooling process, and a second heating process; Preferably, the number of cycles is 1 to 6.

5. The method for controlling residual stress in aluminum-based composite materials according to claim 4, characterized in that, The specific steps of sequentially performing the first heating treatment, the cooling treatment, and the second heating treatment include: The cryogenically treated blank is heated from room temperature to a first set temperature, then cooled to a second set temperature, and then heated back to room temperature. Preferably, the first set temperature is the highest service environment temperature ±5℃; the second set temperature is the lowest service environment temperature ±5℃. Preferably, the heating rate and the cooling rate are the same.

6. The method for controlling residual stress in aluminum-based composite materials according to claim 1, characterized in that, In step 1), the reinforcement in the aluminum-based composite preform is SiC micron-sized ceramic particles and / or B4C micron-sized ceramic particles; and / or The volume content of the reinforcement in the aluminum matrix composite preform is 10% to 75%; and / or The matrix in the aluminum-based composite material blank is one of the 1-series to 7-series aluminum alloys.

7. The method for controlling residual stress in aluminum-based composite materials according to claim 6, characterized in that, The maximum dimension of the aluminum-based composite material blank is L; When L≤100mm, the cryogenic treatment time t=30+5×lnL; When L > 100 mm, the cryogenic treatment time t = 30 + 12 × lnL.

8. The method for controlling residual stress in aluminum-based composite materials according to claim 7, characterized in that, The surface roughness change ΔRZ of the aluminum-based composite material after residual stress regulation before and after service is less than 0.01 μm.

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