Simulation waveform and residual life prediction method for high-temperature component overload damage

Abstract

This invention relates to a method for simulating waveforms and predicting the remaining service life of high-temperature components under overload damage, belonging to the field of material life prediction technology under complex high-temperature loads. The steps are as follows: under the same temperature and load-holding stress conditions, the creep fatigue cycle life of the material is determined through two sets of repeated stress-strain mixed-controlled creep fatigue interactive tests; a creep fatigue damage evolution equation considering the overload effect is constructed based on the proportion of the creep fatigue cycle life; a viscoplastic constitutive model coupled with continuous damage mechanics is established; the viscoplastic constitutive model coupled with continuous damage mechanics is solved in the UMAT subroutine of the ABAQUS platform; and the remaining creep fatigue life of the component is calculated using the viscoplastic constitutive model in the ABAQUS platform. This invention, through the designed HCFIO overload damage simulation waveform, accurately reproduces the entire overload-holding-recovery service process of high-temperature components under single-failure conditions, solving the problem that existing tests cannot simulate real overload scenarios.

Description

Technical Field

[0001] This invention relates to the simulation waveform and remaining life prediction method for overload damage of high-temperature components, and belongs to the field of material life prediction technology under high-temperature complex loads. Background Technology

[0002] In the field of aero-engines, hot-end components such as turbine disks operate under harsh environments of high temperature and high stress, requiring compliance with the ETOPS regulations' OEI (One Engine Inoperative) requirement. This means that when one engine is not operating, another engine must run at maximum continuous thrust for a period of time. Under these conditions, the turbine disk not only suffers creep fatigue damage under normal operating conditions but also experiences additional creep damage due to high constant stress, leading to performance degradation and increased failure risk after long-term service. Existing technologies, such as the Manson-Halford model, while considering load sequence effects, do not account for damage interactions between loads, resulting in lower accuracy and a bias towards non-conservative predictions under multi-level loads. Furthermore, existing tests lack dedicated simulation waveforms for overload damage at different service stages of high-temperature components, failing to accurately reproduce the damage evolution process under conditions such as single-engine failure, thus hindering accurate assessment of remaining service life. Therefore, there is an urgent need to develop test waveforms that can simulate real overload damage and a life prediction method that considers damage interactions. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method for simulating the waveform and predicting the remaining life of high-temperature components under overload conditions. The aim is to accurately simulate the damage process of high-temperature components under overload conditions, improve the accuracy of remaining life prediction, and provide technical support for the safe operation of high-temperature components.

[0004] The present invention adopts the following technical solution: The simulation waveform and remaining life prediction method for overload damage of high-temperature components described in this invention comprises the following steps: Step S1: Under the same temperature and load stress conditions, determine the creep fatigue cycle life of the material through two sets of repeated stress-strain mixed-control creep fatigue interactive tests. N f， A conservative value was selected as the baseline lifespan. Step S2: Set the creep fatigue cycle life. N f The ratio, combined with the creep fatigue interaction test in step S1, is used to design the creep fatigue loading simulation waveform of the overload effect, and the creep fatigue interaction test with stress-strain hybrid control is carried out again. Step S3: Based on the experimental data of the creep fatigue interaction test obtained in Step S3, construct a creep fatigue damage evolution equation that considers the influence of overload. Step S4: Establish a viscoplastic constitutive model for coupled continuous damage mechanics; Step S5: Solve the viscoplastic constitutive model of coupled continuous damage mechanics in the UMAT subroutine of the ABAQUS platform; Step S6: Based on the creep fatigue loading simulation waveform of the overload effect in step S2, the remaining creep fatigue life of the component is calculated using the viscoplastic constitutive model in the ABAQUS platform.

[0005] The simulation waveform and remaining life prediction method for overload damage of high-temperature components described in this invention, in step S2, sets the creep fatigue cycle life as the basis. N f The proportion is: 10% N f 25% N f 50% N f 65% N f Or 70% N f .

[0006] The simulation waveform and remaining life prediction method for overload damage of high-temperature components described in this invention are divided into three stages: before overload, overload, and load maintenance. In the pre-overload stage, the specimens were subjected to creep fatigue alternating test loads. N Loading in one loop; Should N 1 corresponds to a creep fatigue interaction test life ratio of 10%. N f 25% N f 50% N f 65% N f Or 70% N f ; During the overload and hold-load phases, overload stress is applied and the hold-load period is set. After the overload phase, the creep fatigue interactive test loading is restored until the specimen fails.

[0007] The method for simulating waveforms and predicting remaining life of high-temperature component overload damage described in this invention, in step S3, constructs a creep fatigue damage evolution equation based on the theory of continuous damage mechanics, and uses strain-controlled low-cycle fatigue with fatigue damage test values ​​using the cyclic stress range as the damage parameter, as expressed in the following formula:

[0008] In the formulaD f Represents fatigue damage. Corresponding to the cyclic stress of the material, This is the steady-state cyclic stress of the material; The theoretical value of fatigue damage is calculated as follows:

[0009] In the formula N Expressing the number of fatigue cycles, N f For fatigue life; Fatigue damage evolution parameters are determined based on fatigue damage test values ​​and theoretical calculations. α The value of 1 is used to establish the law of fatigue damage accumulation, expressed as follows:

[0010] In the formula, E For elastic modulus, It is an inelastic strain rate. This is the triaxiality factor (this value is 1 for uniaxial tests). σ e For equivalent stress, D f For fatigue damage, S These are parameters related to fatigue damage, and their specific values ​​need to be determined through fatigue test data.

[0011] The method for simulating waveforms and predicting remaining life of high-temperature component overload damage described in this invention is based on fatigue damage test values, theoretical fatigue damage values, and fatigue damage accumulation laws, combined with measured data from creep fatigue interaction tests, to construct a creep damage accumulation model, expressed as follows:

[0012] In the formula, Represents the steady-state creep rate. The creep stress corresponds to the creep stress during the test process, B is the material characteristic constant of the second stage of creep, and n is the creep exponent; Creep damage parameters in creep tests include creep strain rate and theoretical creep damage value; The creep damage test measurement value with creep strain rate as the damage parameter is expressed as follows:

[0013] In the formula, Represents the degree of creep damage. The creep rate corresponding to the third stage of creep; The theoretical value of creep damage is calculated as follows:

[0014] In the formula t The creep duration, t r The creep life of the material; The correlation expression between the theoretical value of creep damage and creep time during the creep test is as follows:

[0015] in, σ Represents the creep stress applied during the test. R v This is the triaxiality factor (this value is 1 in uniaxial test scenarios). A Both 1 and r are parameters related to creep damage; Based on the fatigue and creep tests conducted, and using Lemaitre's continuous damage mechanics theory, a creep fatigue damage evolution equation was established. The damage accumulation in the creep fatigue test can be expressed as:

[0016] In the formula, D The total damage in the creep fatigue test. A 1 represents parameters related to creep damage.

[0017] The method for simulating waveforms and predicting remaining life of high-temperature component overload damage described in this invention is based on a unified viscoplastic constitutive theory, establishing a viscoplastic constitutive model equation coupled with continuous damage mechanics. (1) The master equation includes strain tensor decomposition, and its expression is as follows:

[0018] The expression for the stress tensor is as follows: The expression for inelastic strain with damage is as follows: The expression for the damaged yield surface is as follows:

[0019] In the formula, This is the total strain tensor; It is the elastic strain tensor; It is an inelastic strain tensor; It is an inelastic strain rate; It is a fourth-order elastic tensor; For stress tensor; For back stress tensor; It is the deviatoric stress tensor; K andn Material parameters that characterize the viscosity of a material; F y It is the yield surface function; the material will only generate new inelastic strain when it is greater than 0. R Characterize the isotropic hardening properties of materials; The initial yield stress of the material; For the Macaulay function, its meaning is: when x When ≤0, ,when x When >0, ; D The total damage in the creep fatigue test; (2) The kinematic hardening equation decomposes the back stress into two terms that express the evolution of the back stress. The evolution equation is as follows:

[0020]

[0021]

[0022]

[0023]

[0024] In the above formula C i and (i=1, 2) control the hardening modulus and dynamic recovery rate respectively, and m characterizes the sensitivity of temperature to thermal activation energy. Let λ and δ be the plastic history correction function for the dynamic recovery coefficient and the plastic history evolution function for the static recovery coefficient, respectively, where λ and δ are material parameters, and τ0 is the critical threshold of thermal recovery stress. Let be the plastic history evolution function of the static restitution coefficient. In this context, ϕ and ω are material parameters, where ϕ is the saturation value of static recovery and ω controls the decay rate of static recovery. J ( α 2) The function is to transform the back stress in tensor form α 2 is converted to the equivalent size of a scalar; This is the Mises equivalent inelastic strain rate; α 1. Based on the classic Armstrong-Frederick model, it corresponds to the rate-independent kinematic hardening of short-range, rapid saturation, and captures the transient hardening of small strain cycles and low-cycle fatigue; α2 corresponds to long-range, slow-saturation, time-dependent static recovery kinematic hardening, describing the deformation behavior under high-temperature creep, stress relaxation, and long-term cycling with large strain.

[0025] (3) The isotropic hardening equation describes the translation of the yield surface in stress space, corresponding to the Bauschinger effect and ratcheting behavior. The specific expression is as follows:

[0026] In the formula, R Hardening amount ，b For hardening rate parameters, Q Represents the asymptotic value of isotropic hardening. Q r It is the asymptotic value reflecting incomplete recovery. and m r It is a time-related parameter. A Material parameters; (4) The memory surface equation is used to describe the memory effect of materials on historical plastic deformation, solving problems such as multiaxial non-proportional loading hardening and cyclic loading history correlation that cannot be accurately simulated by classical constitutive models. The memory surface equation is expressed as follows:

[0027] in, F ζ is the loading function of the memory surface, which is the core criterion for determining whether the memory surface has evolved; ζ is the center tensor of the memory surface, which describes the translation position of the memory surface in the strain space and records the directional information of the loading history. The radius of the memory surface describes its size in strain space and records the amplitude of the maximum plastic deformation in history; H(F) is the Heaviside step switch function, which controls the evolution of the memory surface only under specific loading conditions; J 2(⋅) is the Mises equivalent value (equivalent change) of the tensor, which transforms the second-order tensor into a scalar equivalent value; n It is the unit direction tensor of inelastic strain, describing the direction of the current plastic flow; n * represents the outward normal unit tensor of the memory surface, used to describe the direction of the memory surface's evolution. Beneficial effects

[0028] The simulation waveform and remaining life prediction method for overload damage of high-temperature components of the present invention accurately reproduces the entire process of overload-maintenance-recovery service of high-temperature components under single-failure conditions by using the designed HCFIO overload damage simulation waveform, thus solving the problem that existing tests cannot simulate real overload scenarios.

[0029] The simulation waveform and remaining life prediction method for overload damage of high-temperature components of the present invention couples a continuous damage mechanical damage model with a unified viscoplastic constitutive model, and captures the nonlinear interaction effect of creep damage and fatigue damage. It takes into account the changes in material properties with cyclic loading in the damage evolution process, and avoids the limitations of single damage superposition.

[0030] The simulation waveform and remaining life prediction method for high-temperature component overload damage of the present invention significantly improves the prediction accuracy. Through HCFIO test verification, the prediction result error of the present invention is controlled within 1.5 times the error band. Compared with the traditional linear damage accumulation method (maximum error within 5 times), the accuracy and conservatism are greatly improved.

[0031] The present invention provides a method for simulating waveforms and predicting remaining life of high-temperature components under overload damage. This method is simple to operate and computationally convenient, and model parameters can be determined based on conventional test data without requiring additional complex specialized tests, making it highly practical for engineering applications. It provides reliable technical support for the full life-cycle safety assessment of hot-end components in high-temperature equipment, and can effectively guide equipment maintenance, repair, and life-extending decisions. Attached Figure Description

[0032] Figure 1 This is a flowchart of the method in an embodiment of the present invention.

[0033] Figure 2 This is a strain-time and stress-time relationship diagram in an embodiment of the present invention.

[0034] Figure 3 This is a creep fatigue loading waveform with overload effect designed in an embodiment of the present invention.

[0035] Figure 4 To validate the ABAQUS constitutive model.

[0036] Figure 5 The figure shows the remaining lifetime prediction results of the traditional linear damage accumulation method.

[0037] Figure 6 This is a graph showing the remaining lifetime prediction results in an embodiment of the present invention. Detailed Implementation

[0038] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0039] The present invention provides a method for simulating waveforms of overload damage to high-temperature components and predicting remaining life, using GH4169 high-temperature alloy turbine disk material as an example to illustrate the specific implementation process of the present invention: Step S1: Take several samples of GH4169 high-temperature alloy and conduct strain-controlled fatigue tests on some samples at the same temperature with the same strain rate but different strain amplitudes to obtain fatigue test data (GB / T26077-2021 "Metallic Materials Fatigue Test Axial Strain Control Method") to determine fatigue damage parameters; conduct creep tests on some samples at the same temperature as the strain-controlled fatigue test with different stresses (GB / T2039-2024 "Metallic Materials Uniaxial Tensile Creep Test Method").

[0040] Creep test data were acquired to determine creep damage parameters. Two sets of repeated HCFI tests were conducted at 650℃ and 800MPa, with stress-strain hybrid controlled creep fatigue alternating load. The cycle lives were measured to be 1228 and 1566 cycles, respectively. A conservative value of 1200 cycles was selected as the baseline life. N f Proceed to step S2.

[0041] Step S2, design the HCFIO loading waveform, with the following specific parameters: cyclic loading strain range Δ ε t =1.2%, holding time t d =600 s, load stress σ d =600 MPa, the same as the HCFI test, overload stress σ ov =800 MPa.

[0042] At 10% of the HCFI lifespan N f 25% N f 50% N f and 65% N f Phased HCFIO trials: (1) Pre-overload stage: The specimen completes the corresponding number of cyclic loadings under HCFI load; (2) Overload and hold-load stage: Apply overload stress and hold load for 180 minutes to simulate the continuous operation process of the turbine disk transitioning from cruise state to maximum continuous thrust (MCT) state when a single engine fails, so as to meet the requirement of continuous operation for 180 minutes after a single engine failure in the ETOPS code. (3) Post-overload stage: Restore HCFI loading until the sample fails.

[0043] Based on the designed HCFIO loading waveform, conduct an experiment at 650℃, record the remaining number of cycles, and proceed to step S3.

[0044] Step S3, for strain-controlled low-cycle fatigue, fatigue damage is determined as follows: The following are practical fatigue damage test values ​​used to characterize the cyclic stress range as a damage parameter. (1) In the formula D f Represents fatigue damage. Corresponding to the cyclic stress of the material, This is the steady-state cyclic stress of the material.

[0045] The following formula is the theoretical expression for calculating fatigue damage: (2) in, N Indicates the number of fatigue cycles. N f The fatigue life is given by the fatigue damage test values ​​from equation (1) and the theoretical calculation values ​​from equation (2). α The value of 1.

[0046] The following formula describes the cumulative law of fatigue damage: (3) In the formula, E It is the elastic modulus; It is an inelastic strain rate. This is the triaxiality factor (this value is 1 for uniaxial tests). σ e For equivalent stress, S These are parameters related to fatigue damage, and their specific values ​​need to be determined through fatigue test data.

[0047] Based on the measured data collected from creep tests, the Norton equation was constructed. At the same time, creep strain rate was selected as the damage characterization index to clarify the relevant parameters of creep damage evolution. Based on Lemaitre's continuous damage mechanics theory, a creep damage accumulation model was established. The constructed Norton equation is shown in equation (4).

[0048] (4) In the formula, Represents the steady-state creep rate. The creep stress corresponds to the creep stress during the test process. B is the material characteristic constant of the second stage of creep, and n is the creep exponent. The specific values ​​of both need to be determined by fitting the creep test data.

[0049] For creep testing, creep damage parameters are determined as follows: The following formula is used to determine the measured value of creep damage test with creep strain rate as the damage parameter. (5) In the formula, Represents the degree of creep damage. The creep rate corresponding to the third stage of creep.

[0050] The following formula is the theoretical calculation expression for creep damage, where t The creep duration, t r Given the creep life of the material, the creep damage evolution parameter α2 can be determined by combining the creep damage test value of Equation (5) with the theoretical calculation value of Equation (6).

[0051] (6) The following formula describes the correlation between creep damage and creep time during creep testing: (7) In the formula, σ Represents the creep stress applied during the test. R v This is the triaxiality factor (this value is 1 in uniaxial test scenarios). A Both 1 and r are parameters related to creep damage, and their specific values ​​need to be determined based on the creep life and creep stress data in the creep test.

[0052] Based on the fatigue and creep tests conducted, and using Lemaitre's continuous damage mechanics theory, a creep fatigue damage evolution equation was established. The damage accumulation in the creep fatigue test can be expressed as: (8) in, DThe total damage in the creep fatigue test is calculated, then proceed to step S4.

[0053] Step S4: Based on the unified viscoplastic constitutive theory, the following viscoplastic constitutive model equations coupled with continuous damage mechanics are established: (1) The main governing equations include the expression for strain decomposition, stress tensor, inelastic strain with damage, and yield surface with damage.

[0054] (9) (10) (11) (12) in, This is the total strain tensor; It is the elastic strain tensor; It is an inelastic strain tensor; It is an inelastic strain rate; It is a fourth-order elastic tensor; For stress tensor; For back stress tensor; It is the deviatoric stress tensor; K and n Material parameters that characterize the viscosity of a material; Represents the trace of the stress tensor; F y It is the yield surface function; the material will only generate new inelastic strain when it is greater than 0. R Characterize the isotropic hardening properties of materials; This represents the initial yield stress of the material. For the Macaulay function, its meaning is: when x When ≤0, ,when x When >0, .

[0055] (2) The kinematic hardening equation decomposes the back stress into two terms that express the evolution of the back stress, where α 1. Based on the classic Armstrong-Frederick model, it corresponds to the rate-independent kinematic hardening of short-range, rapid saturation, and captures the transient hardening of small strain cycles and low-cycle fatigue; α 2 corresponds to long-range, slow-saturation, time-dependent static recovery kinematic hardening, describing the deformation behavior under high-temperature creep, stress relaxation, and long-term cycling with large strain.

[0056] (13) (14) (15) (16) (17) (18) In the formula C i and (i=1, 2) control the hardening modulus and dynamic recovery rate respectively, and m characterizes the sensitivity of temperature to thermal activation energy. λ is the plastic history correction function for the dynamic recovery coefficient, and δ is the plastic history evolution function for the static recovery coefficient; τ0 is the critical threshold of thermal recovery stress. Let be the plastic history evolution function of the static restitution coefficient. In this context, ϕ and ω are material parameters, where ϕ is the saturation value of static recovery and ω controls the decay rate of static recovery. J ( α 2) The function is to transform the back stress in tensor form α 2 is converted to the equivalent size of a scalar; This is the Mises equivalent inelastic strain rate.

[0057] (3) The isotropic hardening equation describes the translation of the yield surface in stress space, corresponding to the Bauschinger effect and ratcheting behavior, as specifically stated below: (19) (20) in, R Hardening amount ，b For hardening rate parameters, Q The asymptotic value representing the amount of isotropic hardening. Q r It is an asymptotic value that reflects incomplete recovery. and m r It is a time-related parameter. A These are material parameters.

[0058] (4) The memory surface equation is used to describe the memory effect of materials on historical plastic deformation, and solves the problems that classical constitutive models cannot accurately simulate, such as the additional hardening of multiaxial non-proportional loading and the historical correlation of cyclic loading. The specific expression is as follows: (twenty one) (twenty two) (twenty three) (twenty four) (25) (26) (27) in, F The loading function of the memory surface is the core criterion for determining whether the memory surface has evolved; ζ is the center tensor of the memory surface, which describes the translation position of the memory surface in the strain space and records the directional information of the loading history; The radius of the memory surface describes its size in strain space and records the amplitude of the maximum plastic deformation in history. H(F) is the Heaviside step switch function, which controls the evolution of the memory surface only under specific loading conditions; J 2(⋅) is the Mises equivalent value (equivalent change) of the tensor, which transforms the second-order tensor into a scalar equivalent value; n It is the unit direction tensor of inelastic strain, describing the direction of the current plastic flow; n * represents the outward normal unit tensor of the memory surface, describing the direction of the memory surface's evolution.

[0059] Step S5: Based on the established viscoplastic constitutive model of coupled continuous damage mechanics, the viscoplastic constitutive model is solved using the UMAT subroutine in ABAQUS software, and then proceed to step S2. Step S6: Based on the designed load waveform, load is applied in ABAQUS software. A hexahedral linear element model with a side length of 1mm is established, and symmetric constraint boundary conditions are applied on three orthogonal symmetry planes. The load is applied in the Z-axis direction. Specific geometric model and boundary condition settings are as follows: Figure 4 As shown. Applying different types of loads, such as fatigue cyclic loads and creep loads, in the Z-axis normal direction can simulate the deformation behavior and damage evolution of the material throughout its lifespan. After the simulation, the remaining creep fatigue life of the component is calculated. Figure 6 As shown.

[0060] Compared with the prior art, the significant advantages of this embodiment are: (1) The innovative design includes three stages of HCFIO test waveforms: pre-overload, overload and load maintenance, and post-overload. This can simulate the overload condition of the turbine disk transitioning from cruise state to maximum continuous thrust (MCT) state when a single engine fails. (2) Breaking through the shortcomings of the traditional linear damage accumulation method that does not consider damage coupling, the constitutive model of coupled damage can capture the transient plastic strain accumulation behavior in real time through the viscoplastic flow equation to calculate the damage evolution, reflecting the influence of loading history on damage accumulation, and the damage calculation logic is more in line with the essence of material damage evolution.

[0061] (3) This method is simple to calculate and has a clear damage calculation process. It can be directly applied to the life assessment of high-temperature critical components such as turbine disks of aero engines, thus broadening the engineering application scenarios of life prediction methods under high-temperature overload conditions. The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for simulating waveforms and predicting remaining life of overload damage to high-temperature components, characterized in that, The steps are as follows: Step S1: Under the same temperature and load stress conditions, determine the creep fatigue cycle life of the material through two sets of repeated stress-strain mixed-control creep fatigue interactive tests. N f， A conservative value was selected as the baseline lifespan. Step S2: Set the creep fatigue cycle life. N f The ratio, combined with the creep fatigue interaction test in step S1, is used to design the creep fatigue loading simulation waveform of the overload effect, and the creep fatigue interaction test with stress-strain hybrid control is carried out again. Step S3: Based on the experimental data of the creep fatigue interaction test obtained in Step S3, construct a creep fatigue damage evolution equation that considers the influence of overload. Step S4: Establish a viscoplastic constitutive model for coupled continuous damage mechanics; Step S5: Solve the viscoplastic constitutive model of coupled continuous damage mechanics in the UMAT subroutine of the ABAQUS platform; Step S6: Based on the creep fatigue loading simulation waveform of the overload effect in step S2, the remaining creep fatigue life of the component is calculated using the viscoplastic constitutive model in the ABAQUS platform.

2. The method for simulating waveforms and predicting remaining life of high-temperature component overload damage according to claim 1, characterized in that, In step S2, the creep fatigue cycle life is set. N f The proportion is: 10% N f 25% N f 50% N f 65% N f Or 70% N f .

3. The method for simulating waveforms and predicting remaining life of high-temperature component overload damage according to claim 1 or 2, characterized in that, The creep fatigue loading simulation waveform is divided into three stages: before overload, overload, and load holding. In the pre-overload stage, the specimens were subjected to creep fatigue alternating test loads. N Loading in one loop; Should N 1 corresponds to a creep fatigue interaction test life ratio of 10%. N f 25% N f 50% N f 65% N f Or 70% N f ; During the overload and hold-load phases, overload stress is applied and the hold-load period is set. After the overload phase, the creep fatigue interactive test loading is restored until the specimen fails.

4. The method for simulating waveforms and predicting remaining life of high-temperature component overload damage according to claim 1, characterized in that, In step S3, a creep fatigue damage evolution equation is constructed based on the theory of continuous damage mechanics. The strain-controlled low-cycle fatigue, with the fatigue damage test value using the cyclic stress range as the damage parameter, is expressed as follows: ； In the formula D f Represents fatigue damage. Corresponding to the cyclic stress of the material, This is the steady-state cyclic stress of the material; The theoretical value of fatigue damage is calculated as follows: ； In the formula N Expressing the number of fatigue cycles, N f For fatigue life; Fatigue damage evolution parameters are determined based on fatigue damage test values ​​and theoretical calculations. α The value of 1 is used to establish the law of fatigue damage accumulation, expressed as follows: ； In the formula, E For elastic modulus, It is an inelastic strain rate. This is the triaxiality factor (this value is 1 for uniaxial tests). σ e For equivalent stress, D f For fatigue damage, S These are parameters related to fatigue damage, and their specific values ​​need to be determined through fatigue test data.

5. The method for simulating waveforms and predicting remaining life of high-temperature component overload damage according to claim 1 or 4, characterized in that, Based on fatigue damage test values, theoretical fatigue damage values, and fatigue damage accumulation laws, combined with measured data from creep fatigue interaction tests, a creep damage accumulation model is constructed, expressed as follows: ； In the formula, Represents the steady-state creep rate. The creep stress corresponds to the creep stress during the test process, B is the material characteristic constant of the second stage of creep, and n is the creep exponent; Creep damage parameters in creep tests include creep strain rate and theoretical creep damage value; The creep damage test measurement value with creep strain rate as the damage parameter is expressed as follows: ； In the formula, Represents the degree of creep damage. The creep rate corresponding to the third stage of creep; The theoretical value of creep damage is calculated as follows: ； In the formula t The creep duration, t r The creep life of the material; The correlation expression between the theoretical value of creep damage and creep time during the creep test is as follows: ； in, σ Represents the creep stress applied during the test. R v It is a triaxiality factor. A Both 1 and r are parameters related to creep damage; Based on the fatigue and creep tests conducted, and using Lemaitre's continuous damage mechanics theory, a creep fatigue damage evolution equation was established. The damage accumulation in the creep fatigue test can be expressed as: ； In the formula, D The total damage in the creep fatigue test. A 1 represents parameters related to creep damage.

6. The method for simulating waveforms and predicting remaining life of high-temperature component overload damage according to claim 1, characterized in that, Based on the unified viscoplastic constitutive theory, the main governing equations of the viscoplastic constitutive model coupled with continuous damage mechanics are established; The governing equations include strain tensor decomposition, expressed as follows: ； The expression for the stress tensor is as follows: ； The expression for inelastic strain with damage is as follows: ； The expression for the damaged yield surface is as follows: ； In the formula, This is the total strain tensor; It is the elastic strain tensor; It is an inelastic strain tensor; It is an inelastic strain rate; It is a fourth-order elastic tensor; For stress tensor; For back stress tensor; It is the deviatoric stress tensor; K and n Material parameters that characterize the viscosity of a material; F y It is the yield surface function; the material will only generate new inelastic strain when it is greater than 0. R Characterize the isotropic hardening properties of materials; The initial yield stress of the material; For the Macaulay function, its meaning is: when x When ≤0, ,when x When >0, ; D This represents the total damage during the creep fatigue test. The kinematic hardening equation decomposes the back stress into two terms expressing the evolution of the back stress, as shown in the following equation: ； ； ； ； ； ； In the above formula C i and (i=1, 2) control the hardening modulus and dynamic recovery rate respectively, and m characterizes the sensitivity of temperature to thermal activation energy. Let λ and δ be the plastic history correction function for the dynamic recovery coefficient and the plastic history evolution function for the static recovery coefficient, respectively, where λ and δ are material parameters, and τ0 is the critical threshold of thermal recovery stress. Let be the plastic history evolution function of the static restitution coefficient. p For plastic strain, In this context, ϕ and ω are material parameters, where ϕ is the saturation value of static recovery and ω controls the decay rate of static recovery. J ( α 2) The function is to transform the back stress in tensor form α 2 is converted to the equivalent size of a scalar; This is the Mises equivalent inelastic strain rate; The isotropic hardening equation describes the translation of the yield surface in stress space, corresponding to the Bauschinger effect and ratcheting behavior, and is specifically expressed as follows: ； ； In the formula, R Hardening amount ，b For hardening rate parameters, Q Represents the asymptotic value of isotropic hardening. Q r It is the asymptotic value reflecting incomplete recovery. and m r It is a time-related parameter. A Material parameters; The equation for the memory surface, used to describe the memory effect of a material on its historical plastic deformation, is expressed as follows: ； ； ； ； ； ； ； in, F ζ is the loading function for the memory surface, and the core criterion for determining whether the memory surface has evolved; ζ is the center tensor of the memory surface. The radius of the memory surface describes its size in strain space and records the amplitude of the maximum plastic deformation in history; H(F) is the Heaviside step switch function, which controls the evolution of the memory surface only under specific loading conditions; J 2(⋅) is the Mises equivalent value of the tensor, which transforms the second-order tensor into a scalar equivalent value; n It is the unit direction tensor of inelastic strain, describing the direction of the current plastic flow; n * represents the outward normal unit tensor of the memory surface, used to describe the direction of the memory surface's evolution.

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