Monocrystal high-temperature alloy yield strength prediction method considering overheating

Abstract

The invention relates to a single-crystal high-temperature alloy yield strength prediction method considering overheating. The method comprises the following steps: acquiring material parameters of a sample at different temperatures; the volume fraction and the average particle size of the primary gamma'phase and the secondary gamma 'phase of the sample under the overheating working condition are obtained through characterization; based on an Orowan mechanism, according to the volume fraction and the average particle size of the primary gamma'phase, constructing an Orowan model; respectively substituting the material parameters of the sample before and after overheating into an Orowan model to respectively obtain a first contribution of primary gamma'relative yield strength in the sample without overheating and a second contribution of primary gamma 'relative yield strength in the sample after overheating; on the basis of an Orowan mechanism and a dislocation shearing mechanism, according to the volume fraction and the average particle size of the secondary gamma'phase, calculating a third contribution of the secondary gamma 'relative yield strength in the sample; and constructing a yield strength prediction model based on the first contribution, the second contribution, the third contribution and the yield strength of the sample in the non-overheating standard state.

Description

Technical Field

[0001] The present application relates to the technical field of strength prediction of nickel-based single crystal high-temperature alloys, and in particular to a method for predicting the yield strength of single crystal high-temperature alloys taking overheating into consideration. Background Art

[0002] Aircraft engines are subjected to extreme high temperature and high pressure environments during their service. In some special cases, an engine may experience a single engine inoperative (OEI, One Engine Inoperative), that is, due to the failure of one engine, the remaining engines are required to provide short-term high power output to ensure flight safety. At this time, the operating temperature of key engine components rises sharply, resulting in overheating. This overheating process will cause changes in the microstructure and mechanical properties of the material, which will directly affect the structural strength of the hot end components of the engine.

[0003] At present, nickel-based single crystal superalloys have been widely used in key hot-end components of aero-engines, such as turbine blades, due to their excellent high-temperature mechanical properties and oxidation resistance. In engine overheating conditions, the microstructure of nickel-based superalloys will change due to the dissolution and rafting of the strengthening phase and cooling recovery; for example, the matrix channels will increase, the strengthening phase will be directional coarsened, and fine and dispersed secondary phases will precipitate. However, to date, there is still a lack of prediction methods for the yield strength of nickel-based single crystal superalloys under overheating conditions, and there is no suitable theory to parameterize these microstructural evolution effects to link the macroscopic mechanical properties of the alloy. Therefore, establishing a method that can predict the yield strength of superalloys under OEI overheating conditions is of great significance for ensuring the safety of aero-engines under extreme conditions. Summary of the invention

[0004] Based on this, it is necessary to provide a single crystal high temperature alloy yield strength prediction method based on precipitation strengthening theory, which can quickly predict the yield strength of such alloys at different overheating temperatures and is applicable to a larger range of overheating stress levels and overheating times. Specifically, a single crystal high temperature alloy yield strength prediction method considering overheating includes: S1: Obtaining material parameters of a sample at different temperatures, wherein the sample is a nickel-based single crystal high-temperature alloy; The material parameters of the samples at different temperatures include yield strength, shear modulus, antiphase domain boundary energy, Burgers vector and Poisson's ratio; S2: Through characterization, the sample is obtained once under overheating conditions c 'Phase and quadratic c 'Volume fraction and average particle size of the phase; S3: Based on the Orowan mechanism, and according to a cThe volume fraction and average particle size of the phase were used to construct the Orowan model; the material parameters of the sample before and after overheating were respectively substituted into the Orowan model to obtain the volume fraction and average particle size of the sample before and after overheating. c 'The first contribution to the relative yield strength, the first c 'The second contribution to the relative yield strength; the expression of the Orowan model is: ; ; in, Indicates once c 'Precipitation strengthening stress value relative to yield strength contribution; Bypass once c 'The critical shear stress value required for the phase; m represents the Schmid factor; G It represents the shear modulus of the sample at different temperatures; v represents the Poisson's ratio of the sample at different temperatures; b represents the Burgers vector of the sample at different temperatures; Indicates once c 'The average particle size of the phase; Indicates once c 'The average spacing of the phases; Indicates once c 'Volume fraction of phase; S4: Based on the Orowan mechanism and dislocation shear mechanism, and according to the secondary c 'The volume fraction and average particle size of the phase are calculated to determine the secondary c 'The third contribution to relative yield strength; S5: Based on the first contribution, the second contribution, the third contribution and the yield strength of the sample in the standard state without overheating, a yield strength prediction model considering overheating is constructed.

[0005] Preferably, in S2, the characterization includes: The samples were statistically analyzed by scanning electron microscope / transmission electron microscope and electron backscatter diffraction analyzer under overheating conditions. c 'Phase and quadratic c ' Phase volume fraction and average particle size.

[0006] Preferably, count once c The number of SEM / TEM photos used to measure the volume fraction and average particle size of the phase is not less than 5, and each photo contains at least one c The number of particles of the 'phase is not less than 500; Statistics Secondary cThe phase volume fraction and average particle size selected by the phase precipitation aggregation area are not less than 5, and each secondary c The number of particles of the 'phase is not less than 50.

[0007] Preferably, S4 includes: According to the secondary c The volume fraction and average particle size of the phase, as well as the shear modulus, Poisson's ratio, Burgers vector, and antiphase boundary energy of the sample at different temperatures, are used to calculate the dislocation cutting through the second c 'The critical shear stress value required for the phase, bypassing the secondary c 'The critical shear stress value required for the phase; Based on the second c 'Particle size of the phase, secondary c The phase has Orowan mechanism and dislocation shear mechanism. The Orowan mechanism corresponds to bypassing the secondary c The critical shear stress value required for the phase, the dislocation shear mechanism corresponds to the dislocation shearing through the second c The critical shear stress required for the phase; the dominance of the two mechanisms depends on the dislocation shearing through the secondary c The critical shear stress value required for bypassing the secondary c 'The magnitude of the critical shear stress value required by the phase; When the dislocation cuts through the second c The critical shear stress required for the phase is greater than or equal to the value of bypassing the secondary c 'When the critical shear stress value required by the phase is greater than , the dominant mechanism is the Orowan mechanism; When the dislocation cuts through the second c The critical shear stress required for the phase is less than the secondary c 'When the critical shear stress value required by the phase is greater than , the dominant mechanism is the dislocation shear mechanism; Based on the critical shear stress value and Schmid factor corresponding to the dominant mechanism, the secondary c 'The third contribution to the relative yield strength.

[0008] Preferably, the dislocation cuts twice c The calculation formula for the critical shear stress value required for the phase is: ; Bypass the Second c The calculation formula for the critical shear stress value required for the phase is: ; in, Indicates that the dislocation has been cut twice c 'The critical shear stress value required for the phase; Bypass the second c 'The critical shear stress value required for the phase;G It represents the shear modulus of the sample at different temperatures; b represents the Burgers vector of the sample at different temperatures; w A constant representing the elastic repulsion between strongly paired dislocations; Represents secondary c 'The average particle size of the phase; Represents secondary c 'Volume fraction of phase; It represents the antiphase domain boundary energy of the sample at different temperatures; C represents the empirical constant; v represents the Poisson's ratio of the sample at different temperatures; represents the dislocation core radius.

[0009] Preferably, the secondary c The third contribution to the relative yield strength is calculated as: ; in, Indicates the secondary c 'The third contribution to relative yield strength; Indicates that the dislocation has been cut twice c 'The critical shear stress value required for the phase; Bypass the second c 'The critical shear stress value required for the phase; m Represents the Schmid factor.

[0010] Preferably, secondary c The particle size of the 'phase is 10~40nm.

[0011] Preferably, the expression of the yield strength prediction model considering overheating is: ; in, Indicates the yield strength of the sample after overheating; It indicates the yield strength of the sample under the standard state without overheating; Indicates that no overheating occurs in the sample once c 'First contribution to relative yield strength; Indicates that the sample is once c 'Second contribution to relative yield strength; Indicates the secondary c 'The third contribution to relative yield strength; The volume fraction of the precipitated phase after overheating, the average particle size and the yield strength of the sample under the standard state without overheating are input into the yield strength prediction model considering overheating to obtain the yield strength of the sample after overheating.

[0012] Beneficial effects: This method is based on c 'Phase precipitation strengthening mechanism, a statistically dependent prediction model is established according to the microstructural changes of single crystal high-temperature alloys before and after overheating, and the yield strength of single crystal high-temperature alloys after overheating is predicted; this method can accurately predict the yield strength of single crystal high-temperature alloys within a large range of overheating stress levels and overheating times, which is of great significance for the strength evaluation of single crystal high-temperature alloys under extreme working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 This is a flow chart of a method for predicting the yield strength of a single crystal high-temperature alloy taking overheating into account in an embodiment of the present application.

[0015] Figure 2 The dominant mechanism and the secondary mechanism in the embodiment of this application c 'Schematic diagram of the relationship between the average particle size of the phase.

[0016] Figure 3 This is a schematic diagram of OEI processing in an embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0018] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0019] like Figure 1 As shown, this embodiment provides a method for predicting the yield strength of a single crystal high-temperature alloy taking overheating into consideration, the method comprising: S1: Obtain material parameters of a sample at different temperatures, wherein the sample is a nickel-based single crystal high-temperature alloy.

[0020] In this embodiment, the material parameters of the sample at different temperatures include but are not limited to: yield strength, shear modulus, antiphase domain boundary energy, Burgers vector and Poisson's ratio.

[0021] S2: Through characterization, the sample is obtained once under overheating conditions c 'Phase and quadratic c ' Phase volume fraction and average particle size.

[0022] Specifically, the characteristics include: The samples were statistically analyzed by scanning electron microscope / transmission electron microscope and electron backscatter diffraction analyzer under overheating conditions. c 'Phase and quadratic c ' Phase volume fraction and average particle size.

[0023] In this embodiment, statistics are counted once c The number of SEM / TEM photos used to measure the volume fraction and average particle size of the phase is not less than 5, and each photo contains at least one c The number of particles of the 'phase is not less than 500; Statistics Secondary c The phase volume fraction and average particle size selected by the phase precipitation aggregation area are not less than 5, and each secondary c The number of particles of the 'phase is not less than 50.

[0024] S3: Based on the Orowan mechanism, and according to a c 'phase volume fraction and average particle size, construct the Orowan model; in this embodiment, the Orowan mechanism includes the shear stress increment calculation formula caused by dislocation bypassing the precipitate phase in the precipitation strengthening theory, which is generally applied to larger precipitate phases (such as a c 'phase), and therefore used it as the basis for constructing the Orowan model; The expression of Orowan model is: ; ; in, Indicates once c 'Precipitation strengthening stress value relative to yield strength contribution; Bypass once c 'The critical shear stress value required for the phase (MPa); m represents the Schmid factor; G represents the shear modulus of the sample at different temperatures (GPa); vrepresents the Poisson's ratio of the sample at different temperatures; b represents the Burgers vector of the sample at different temperatures; Indicates once c 'Average particle size of the phase (nm); Indicates once c 'Average spacing of phases (nm); Indicates once c 'Volume fraction of the phase (%).

[0025] Substitute the material parameters of the sample before and after overheating into the Orowan model to obtain the c 'The first contribution to relative yield strength , after overheating, the sample c 'The second contribution to the relative yield strength .

[0026] S4: Based on the Orowan mechanism and dislocation shear mechanism, and according to the secondary c 'The volume fraction and average particle size of the phase are calculated to determine the secondary c 'The third contribution to relative yield strength; In this embodiment, the Orowan mechanism also includes the shear stress enhancement calculation formula caused by dislocation bypassing the precipitate phase and forming a dislocation in the precipitation strengthening theory, which is applicable to smaller precipitate phases (such as secondary c 'phase), because the smaller precipitate phase makes it easier for dislocations to form loops around the precipitate phase, so this calculation formula is used to calculate the bypass of the secondary c 'The critical shear stress value required for the phase.

[0027] The dislocation shear mechanism includes the calculation formula for the shear stress increment caused by the dislocation shear precipitate phase. The dislocation shear mechanism needs to be considered when the precipitate phase size is smaller than the critical size (for nickel-based single crystal high-temperature alloys, this critical size is generally 10~40nm). c When the phase is approximately in this critical size range, it is necessary to use both the Orowan mechanism and the dislocation shear mechanism in S4, and to compare the numerical values ​​to distinguish which mechanism is dominant.

[0028] Specifically, according to the second c The volume fraction and average particle size of the phase, as well as the shear modulus, Poisson's ratio, Burgers vector, and antiphase boundary energy of the sample at different temperatures, are used to calculate the dislocation cutting through the second c 'The critical shear stress value required for the phase, bypassing the secondary c 'The critical shear stress value required for the phase; Dislocation cut twice cThe calculation formula for the critical shear stress value required for the phase is: ; Bypass the Second c The calculation formula for the critical shear stress value required for the phase is: ; in, Indicates that the dislocation has been cut twice c 'The critical shear stress value required for the phase (MPa); Bypass the second c 'The critical shear stress value required for the phase (MPa); G It represents the shear modulus of the sample at different temperatures; b represents the Burgers vector of the sample at different temperatures; w A constant representing the elastic repulsion between strongly paired dislocations; Represents secondary c 'The average particle size of the phase; Represents secondary c 'Volume fraction of phase; represents the antiphase boundary energy of the sample at different temperatures (J / m 2 ); C represents the empirical constant; v represents the Poisson's ratio of the sample at different temperatures; represents the dislocation core radius (usually taken as twice the Burgers vector).

[0029] Based on the second c 'Particle size of the phase (fine size, particle size is 10~40nm), secondary c The phase has Orowan mechanism and dislocation shear mechanism. The Orowan mechanism corresponds to bypassing the secondary c The critical shear stress value required for the phase, the dislocation shear mechanism corresponds to the dislocation shearing through the second c The critical shear stress required for the phase; the dominance of the two mechanisms depends on the dislocation shearing through the secondary c The critical shear stress value required for bypassing the secondary c The magnitude of the critical shear stress required by the phase, such as Figure 2 As shown; When the dislocation cuts through the second c The critical shear stress required for the phase is greater than or equal to the value of bypassing the secondary c 'When the critical shear stress value required by the phase is greater than , the dominant mechanism is the Orowan mechanism; When the dislocation cuts through the second c The critical shear stress required for the phase is less than the secondary c 'When the critical shear stress value required by the phase is greater than , the dominant mechanism is the dislocation shear mechanism; Based on the critical shear stress value and Schmid factor corresponding to the dominant mechanism, the secondary c 'The third contribution to relative yield strength; The critical shear stress values ​​calculated above are all shear stress increments, so it is necessary to convert the shear stress into a normal stress increment through the Schmid factor to obtain the yield strength value contributed by precipitation strengthening. The calculation formula for the third contribution is: ; in, Indicates the secondary c 'The third contribution to relative yield strength; Indicates that the dislocation has been cut twice c 'The critical shear stress value required for the phase; Bypass the second c 'The critical shear stress value required for the phase; m Represents the Schmid factor.

[0030] S5: Based on the first contribution, the second contribution, the third contribution and the yield strength of the sample in the standard state without overheating, a yield strength prediction model considering overheating is constructed.

[0031] Specifically, the yield strength prediction model is constructed based on two c 'The superposition of phase strengthening effects; for nickel-based single crystal high-temperature alloys, the theoretical value of its yield strength can be calculated by solid solution strengthening + precipitation strengthening. Solid solution strengthening mainly depends on the type and concentration of alloy solute atoms, while precipitation strengthening comes from the strengthening of the alloy c 'phase. Because overheating does not change the proportion and type of alloy elements, it only makes the c 'Phase partially dissolved and fine secondary c 'phase precipitates in large quantities, so the yield strength value of the nickel-based single crystal high-temperature alloy after overheating can be calculated by the difference in precipitation strengthening values ​​of the alloy before and after overheating; c 'Phase divided into once c 'Phase and quadratic c 'phase, so the difference in precipitation strengthening value of the alloy before and after overheating includes the difference between the precipitation strengthening value before and after overheating. c The difference in precipitation strengthening values ​​contributed by the phase , twice before and after overheating c The difference in precipitation strengthening values ​​contributed by the phase (Because the initial alloy has no secondary c 'phase, so the secondary c The precipitation strengthening value of the phase contribution is 0), and the yield strength of the initial alloy is taken as the basic value. cThe yield strength value of the alloy after overheating is deduced from the difference in precipitation strengthening values ​​contributed by the phase before and after overheating, and based on this, a yield strength prediction model considering overheating is constructed.

[0032] The expression of the yield strength prediction model considering overheating is: ; in, Indicates the yield strength of the sample after overheating; It indicates the yield strength of the sample under the standard state without overheating; Indicates that no overheating occurs in the sample once c 'First contribution to relative yield strength; Indicates that the sample is once c 'Second contribution to relative yield strength; Indicates the secondary c 'The third contribution to relative yield strength; The volume fraction of the precipitated phase after overheating, the average particle size and the yield strength of the sample under the standard state without overheating are input into the yield strength prediction model considering overheating to obtain the yield strength of the sample after overheating.

[0033] This embodiment takes nickel-based single crystal high-temperature alloy DD6 as an example to conduct overheating and multiple overheating test experiments with different stress levels. The material parameters involved in the test experiments are shown in Table 1.

[0034] Table 1 is the material parameter table of DD6 high temperature alloy; ; Table 1 shows the various material parameters of DD6 superalloy, where the constant of the elastic repulsive force between strong pairing dislocations is w =1.4, the empirical constant is C =1.

[0035] The DD6 high temperature alloy tensile specimen was subjected to overheat treatment. Figure 3 The specific processing flow of OEI processing is as follows: First, the DD6 high-temperature alloy tensile specimen was slowly heated to 1000°C and kept warm for 3 minutes to simulate the normal service state of the aircraft, and the stress was simultaneously loaded to the OEI stress level. s OEI (This embodiment considers three stress levels, namely s OEI =170MPa, 230MPa, 270MPa), and then rapidly raised to 1100℃ at 60℃ / s for 30s to simulate OEI conditions, and then unloaded the stress and air cooled to room temperature.

[0036] The microstructure characteristics of the DD6 superalloy tensile specimens were photographed using a scanning electron microscope and a transmission electron microscope. The volume fraction and average particle size of the precipitated phase in the DD6 superalloy tensile specimens were measured and statistically obtained. The obtained data are shown in Table 2.

[0037] Table 2 is the data table of DD6 superalloy after OEI treatment at different overheat stress levels and different overheating times; ; Substituting the data in Table 2 into the yield strength prediction model considering overheating, the yield strength of the nickel-based single crystal high-temperature alloy under different overheating stress levels and overheating times is predicted. The prediction results are shown in Table 3.

[0038] Table 3 is the yield strength prediction result table of DD6 superalloy under different overheating conditions; ; It can be seen from Table 3 that the deviation between the predicted results and the experimental results is only within 5%, which shows that the yield strength prediction model considering overheating has effective guiding significance for the strength boundary of DD6 superalloy after OEI, and provides important theoretical guidance and model support for the application of DD6 superalloy under extreme working conditions.

[0039] The single crystal high temperature alloy yield strength prediction method considering overheating provided in this embodiment has the following beneficial effects: 1. This method is based on c 'Phase precipitation strengthening mechanism, based on the microstructural changes of single crystal high temperature alloy before and after overheating, and by coupling once c 'Phase and secondary precipitation after overheating c 'phase strengthening effect, combined with precipitation strengthening theory, established a yield strength prediction model for nickel-based single crystal high-temperature alloys considering overheating. According to the volume fraction of the precipitated phase after overheating, the average particle size and the yield strength under the standard state without overheating of the input test sample, the yield strength of the single crystal high-temperature alloy after overheating is predicted. This method can not only predict the yield strength under different stress levels during overheating, but also predict the yield strength of the single crystal high-temperature alloy after multiple overheating treatments. It is of great significance for the strength evaluation of single crystal high-temperature alloys under extreme working conditions, and provides a scientific basis and theoretical guidance for improving the safety of key components of aero-engines.

[0040] 2. Taking DD6 high-temperature alloy as an example, overheating and multiple overheating tests accompanied by different stress levels were carried out. The qualitative and quantitative relationship of alloy strength was calculated through the yield strength prediction model considering overheating in this method. The results were highly consistent with the experimental data, which provided a scientific basis for the strength evaluation of single crystal high-temperature alloys under extreme working conditions. It has broad promotion value and is of great significance to the evaluation of material safety and reliability.

[0041] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0042] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A method for predicting yield strength of single crystal high temperature alloy considering overheating, characterized in that: include: S1: Obtaining material parameters of a sample at different temperatures, wherein the sample is a nickel-based single crystal high-temperature alloy; The material parameters of the samples at different temperatures include yield strength, shear modulus, antiphase domain boundary energy, Burgers vector and Poisson's ratio; S2: Through characterization, the sample is obtained once under overheating conditions γ 'Phase and quadratic γ 'Volume fraction and average particle size of the phase; S3: Based on the Orowan mechanism, and according to a γ The volume fraction and average particle size of the phase were used to construct the Orowan model; the material parameters of the sample before and after overheating were respectively substituted into the Orowan model to obtain the volume fraction and average particle size of the sample before and after overheating. γ 'The first contribution to the relative yield strength, the first γ 'The second contribution to the relative yield strength; the expression of the Orowan model is: ； ； in, Indicates once γ 'Precipitation strengthening stress value relative to yield strength contribution; Bypass once γ 'The critical shear stress value required for the phase; m represents the Schmid factor; G It represents the shear modulus of the sample at different temperatures; v represents the Poisson's ratio of the sample at different temperatures; b represents the Burgers vector of the sample at different temperatures; Indicates once γ 'The average particle size of the phase; Indicates once γ 'The average spacing of the phases; Indicates once γ 'Volume fraction of phase; S4: Based on the Orowan mechanism and dislocation shear mechanism, and according to the secondary γ 'The volume fraction and average particle size of the phase are calculated to determine the secondary γ 'The third contribution to relative yield strength; S5: Based on the first contribution, the second contribution, the third contribution and the yield strength of the sample in the standard state without overheating, a yield strength prediction model considering overheating is constructed.

2. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 1, characterized in that: In S2, the representations include: The samples were statistically analyzed by scanning electron microscope / transmission electron microscope and electron backscatter diffraction analyzer under overheating conditions. γ 'Phase and quadratic γ ' Phase volume fraction and average particle size.

3. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 2, characterized in that: Count once γ The number of SEM / TEM photos used to measure the volume fraction and average particle size of the phase is not less than 5, and each photo contains at least one γ The number of particles of the 'phase is not less than 500; Statistics Secondary γ The phase volume fraction and average particle size selected by the phase precipitation aggregation area are not less than 5, and each secondary γ The number of particles of the 'phase is not less than 50.

4. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 1, characterized in that S4 include: According to the secondary γ The volume fraction and average particle size of the phase, as well as the shear modulus, Poisson's ratio, Burgers vector, and antiphase domain boundary energy of the sample at different temperatures, are used to calculate the dislocation cutting through the second γ 'The critical shear stress value required for the phase, bypassing the secondary γ 'The critical shear stress value required for the phase; Based on the second γ 'Particle size of the phase, secondary γ The phase has Orowan mechanism and dislocation shear mechanism. The Orowan mechanism corresponds to bypassing the secondary γ The critical shear stress value required for the phase, the dislocation shear mechanism corresponds to the dislocation shearing through the second γ The critical shear stress required for the phase; the dominance of the two mechanisms depends on the dislocation shearing through the secondary γ The critical shear stress value required for bypassing the secondary γ 'The magnitude of the critical shear stress value required by the phase; When the dislocation cuts through the second γ The critical shear stress required for the phase is greater than or equal to the value of bypassing the secondary γ 'When the critical shear stress value required by the phase is greater than , the dominant mechanism is the Orowan mechanism; When the dislocation cuts through the second γ The critical shear stress required for the phase is less than the secondary γ 'When the critical shear stress value required by the phase is greater than , the dominant mechanism is the dislocation shear mechanism; Based on the critical shear stress value and Schmid factor corresponding to the dominant mechanism, the secondary γ 'The third contribution to the relative yield strength.

5. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 4, characterized in that: Dislocation cut twice γ The calculation formula for the critical shear stress value required for the phase is: ； Bypass the Second γ The calculation formula for the critical shear stress value required for the phase is: ； in, Indicates that the dislocation has been cut twice γ 'The critical shear stress value required for the phase; Bypass the second γ 'The critical shear stress value required for the phase; G It represents the shear modulus of the sample at different temperatures; b represents the Burgers vector of the sample at different temperatures; w A constant representing the elastic repulsion between strongly paired dislocations; Represents secondary γ 'The average particle size of the phase; Represents secondary γ 'Volume fraction of phase; It represents the antiphase domain boundary energy of the sample at different temperatures; C represents an empirical constant; v represents the Poisson's ratio of the sample at different temperatures; represents the dislocation core radius.

6. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 5, characterized in that: Secondary γ The third contribution to the relative yield strength is calculated as: ； in, Indicates the secondary γ 'The third contribution to relative yield strength; Indicates that the dislocation has been cut twice γ 'The critical shear stress value required for the phase; Bypass the second γ 'The critical shear stress value required for the phase; m Represents the Schmid factor.

7. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 4, characterized in that: Secondary γ The particle size of the 'phase is 10~40nm.

8. The method for predicting yield strength of single crystal high temperature alloy considering overheating according to claim 6, characterized in that: The expression of the yield strength prediction model considering overheating is: ； in, Indicates the yield strength of the sample after overheating; It indicates the yield strength of the sample under the standard state without overheating; Indicates that no overheating occurs in the sample once γ 'First contribution to relative yield strength; Indicates that the sample is once γ 'Second contribution to relative yield strength; Indicates the secondary γ 'The third contribution to relative yield strength; The volume fraction of the precipitated phase after overheating, the average particle size and the yield strength of the sample under the standard state without overheating are input into the yield strength prediction model considering overheating to obtain the yield strength of the sample after overheating.

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