Life prediction method based on material damage analysis, program product, storage medium and equipment

Abstract

The invention discloses a service life prediction method based on material damage analysis, a program product, a storage medium and equipment, and relates to the technical field of service life prediction.The method comprises the steps that a simulation model of a to-be-detected material is constructed; the simulation model is obtained by writing a constitutive model and a damage model which simultaneously consider creep-fatigue-oxidation damage factors on the basis of a finite element model; solving the simulation model by adopting a finite element solver to obtain a simulation result; the simulation result comprises a damage cumulative distribution cloud picture and a creep-fatigue-oxidation damage value; and carrying out damage analysis and life prediction on the to-be-detected material according to a simulation result. According to the material damage analysis-based life prediction method, the program product, the storage medium and the equipment, the accuracy of material damage analysis and life prediction can be effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of life prediction, and in particular to a life prediction method, program product, storage medium and device based on material damage analysis. Background Art

[0002] In the context of improving energy conversion efficiency and promoting carbon neutrality, power plant units are gradually adopting higher steam temperature and pressure parameters to improve power generation efficiency. However, during actual operation, the components of the generator set will frequently experience cycles of start and stop and violent fluctuations in internal pressure, which can easily cause fatigue failure of the components. It is worth noting that generator sets serve in a long-term high temperature and high pressure environment, and creep fractures are also common. At the same time, key components that operate in a high temperature and corrosive environment for a long time will inevitably undergo oxidation reactions. From the above, it can be seen that the damage caused by creep-fatigue-oxidation has become one of the main reasons for the premature failure of the core components of the generator set. Therefore, it is of great significance to explore and develop accurate creep-fatigue-oxidation damage assessment and life prediction technology.

[0003] The current mainstream creep-fatigue life prediction technology mainly relies on the calculation of damage caused by creep and fatigue, but when equipment components face severe oxidation during actual service, the promotion and use of these life prediction technologies will encounter serious limitations. In addition, unlike smooth round bar specimens, traditional calculation methods can hardly obtain information such as stress-strain response and damage of materials under multi-axial stress states (different positions of geometric discontinuous structures), and cannot accurately judge the damage conditions at different positions of geometric discontinuous structures, which limits the scope of application of the method. Summary of the invention

[0004] The purpose of this application is to provide a life prediction method, program product, storage medium and device based on material damage analysis, which can effectively improve the accuracy of material damage analysis and life prediction.

[0005] To achieve the above-mentioned objectives, the present application provides the following solutions: In the first aspect, the present application provides a life prediction method based on material damage analysis, including: constructing a simulation model of the material to be tested; the simulation model is obtained by writing a constitutive model and a damage model that simultaneously considers creep-fatigue-oxidation damage factors on the basis of a finite element model; using a finite element solver to solve the simulation model to obtain simulation results; the simulation results include a damage cumulative distribution cloud map and creep-fatigue-oxidation damage values; and performing damage analysis and life prediction of the material to be tested based on the simulation results.

[0006] Optionally, the construction of the simulation model of the material to be tested specifically includes: using finite element analysis software ABAQUS to establish a finite element model of the material to be tested containing a notch; writing a constitutive model and a damage model that simultaneously considers creep-fatigue-oxidation damage factors in the subroutine UVARM of the finite element model; the constitutive model includes a creep constitutive model and a cyclic elastic-plastic constitutive model; the damage model includes a creep damage model, a fatigue damage model and an oxidation damage model.

[0007] Optionally, the creep constitutive model is ;in, is the equivalent creep rate of the material to be tested; is the equivalent creep strain of the material to be tested; is the equivalent deviatoric stress of the material to be tested; , and are all temperature-related material parameters; the cyclic elastoplastic constitutive model is ;in, is the total strain rate tensor of the material to be tested; is the elastic strain rate tensor of the material to be tested; is the plastic strain rate tensor of the material to be tested.

[0008] Optionally, the creep damage model is ;in, is the creep damage value for each cycle; For each cycle of the finite element numerical calculation, it increases from 1 to The number of increments; Incremental step The creep damage value corresponding to the cycle after completion; is an incremental step The creep strain energy density dissipation rate after completion; is an incremental step The failure inelastic strain energy density after the end of the test; MDF is the multiaxial creep ductility factor; is the upper plateau of the inelastic strain energy density at failure.

[0009] Optionally, the fatigue damage model is ;in, The fatigue damage value for each week; Incremental step The fatigue damage value of the corresponding week after completion; Incremental step Equivalent plastic strain range after completion; is the peak stress during cyclic loading and unloading; and These are temperature-dependent material parameters.

[0010] Optionally, the oxidative damage model is ;in, is the oxidative damage value for each week; Incremental step The oxidative damage value of the corresponding week after completion; is the radius of the cross section of the material to be tested; is the thickness of the oxidation affected zone of the material to be tested; is the thickness of the oxide on the material to be tested; is the parabolic rate constant; is the oxidation exposure time; The distance from the outer surface of the material to be tested to the outer surface of the material to be tested; is the oxidative damage index; is the maximum value of the oxidative damage index.

[0011] Optionally, the damage analysis and life prediction of the material to be tested based on the simulation results specifically include: performing damage analysis on the material to be tested based on the damage cumulative distribution cloud map in the simulation results to determine the creep-fatigue-oxidation failure position of the material to be tested; predicting the creep-fatigue-oxidation failure life of the material to be tested using a linear damage accumulation criterion based on the creep-fatigue-oxidation damage value in the simulation results .

[0012] In a second aspect, the present application provides a computer program product, including a computer program, which implements the life prediction method based on material damage analysis when executed by a processor.

[0013] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the life prediction method based on material damage analysis.

[0014] In a fourth aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the life prediction method based on material damage analysis.

[0015] According to the specific embodiments provided by the present application, the present application has the following technical effects: the present application provides a life prediction method based on material damage analysis, a program product, a storage medium and a device, which mainly relates to a numerical simulation calculation method for creep-fatigue-oxidation damage assessment and life prediction based on finite element analysis. In order to solve the problem that the traditional calculation method cannot obtain geometric discontinuous structures, such as stress-strain response and damage information at different positions of notches, the present application constructs a simulation model based on finite element analysis to evaluate the creep-fatigue-oxidation damage at different positions of geometric discontinuous structures in real time, including processes such as damage evolution and damage accumulation, and predicts the life based on the analysis of the damage situation. The life prediction method based on material damage analysis of the present application can evaluate the creep-fatigue-oxidation damage of the material to be tested in different geometric size structures and different positions in real time, and can accurately predict the creep-fatigue-oxidation failure position and life of the material to be tested, with the advantages of high reliability, intuitiveness and flexibility. Therefore, the life prediction method, program product, storage medium and device based on material damage analysis of the present application can effectively improve the accuracy of material damage analysis and life prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments 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.

[0017] Figure 1 A schematic diagram of the process flow of the life prediction method based on material damage analysis provided in this application.

[0018] Figure 2 The simulation model and boundary condition diagram provided for this application; wherein, Figure 2 a in the figure is a schematic diagram of the grid unit and boundary conditions of the simulation model with a notch depth of 0.1 mm; Figure 2 b is a schematic diagram of the grid unit and boundary conditions of the simulation model with a notch depth of 0.5 mm; Figure 2 Figure c is a local enlarged schematic diagram of the grid unit at the gap.

[0019] Figure 3 A schematic diagram of the damage ratio of different damage types under different load holding times provided for this application; wherein, Figure 3 a in the figure is a schematic diagram of the damage ratio distribution when the notch depth is 0.1 mm; Figure 3 Figure b is a schematic diagram of the damage ratio distribution when the notch depth is 0.5 mm.

[0020] Figure 4This is a schematic diagram of the life prediction results of the P92 material provided in this application; wherein, Figure 4 a in the figure is a comparison diagram of the notch depth of 0.1 mm under different holding times. Figure 4 Figure b is a schematic diagram of the comparison results of notch depth of 0.5 mm under different holding times.

[0021] Figure 5 The damage cumulative distribution cloud diagram of the simulation model with a notch depth of 0.1 mm provided in this application; wherein, Figure 5 a in the figure is the damage cumulative distribution cloud diagram when the load holding time is 60s; Figure 5 b in the figure is the damage cumulative distribution cloud diagram when the load holding time is 300s; Figure 5 c in the figure is the damage cumulative distribution cloud diagram when the load holding time is 600s; Figure 5 The d in the figure is the damage cumulative distribution cloud diagram when the load holding time is 3600s.

[0022] Figure 6 The damage cumulative distribution cloud diagram of the simulation model with a notch depth of 0.5 mm provided in this application; wherein, Figure 6 a in the figure is the damage cumulative distribution cloud diagram when the load holding time is 60s; Figure 6 b in the figure is the damage cumulative distribution cloud diagram when the load holding time is 600s; Figure 6 Figure c is the damage cumulative distribution cloud diagram when the load holding time is 3600s. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0024] Since traditional calculation methods for life prediction are almost unable to obtain information such as the stress-strain response and damage of materials at different positions of geometrically discontinuous structures under multi-axial stress states, finite element analysis can intuitively provide a feasible method to evaluate the damage evolution of different positions of geometrically discontinuous structures in real time. It can be seen that it is very necessary to develop a numerical calculation method for damage assessment and life prediction based on finite element analysis, which is very important for damage assessment and creep-fatigue-oxidation life prediction of key engineering components, especially geometrically discontinuous structures. Based on this, the present application provides a life prediction method, program product, storage medium and equipment based on material damage analysis to effectively improve the accuracy of material damage analysis and life prediction.

[0025] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0026] like Figure 1 As shown, the present application discloses a life prediction method based on material damage analysis, which specifically includes the following steps.

[0027] Step 1: Build a simulation model of the material to be tested.

[0028] Specifically, first, the present application constructs finite element models of different geometric dimensions and notch depths in the finite element analysis software ABAQUS, that is, establishes a finite element model of the notch of the material to be tested. Based on the constructed finite element model, the constitutive model and damage model required for the finite element analysis simulation calculation of the present application are written into the subroutine UVARM of the finite element model. The constitutive model and damage model simultaneously consider the creep-fatigue-oxidation damage factors.

[0029] Among them, the constitutive model includes a creep constitutive model based on strain hardening and a cyclic elastoplastic constitutive model based on nonlinear kinematic hardening rate, as shown below.

[0030] The present application describes the creep deformation behavior of the material to be tested (hereinafter referred to as the material) at high temperature by establishing a creep constitutive model based on strain hardening to describe the steady-state creep stage. The creep strain rate can be expressed as formula (1).

[0031] (1).

[0032] in, is the equivalent creep rate of the material to be tested; is the equivalent creep strain of the material to be tested; is the equivalent deviatoric stress of the material to be tested; , and These are temperature-dependent material parameters.

[0033] In order to describe the cyclic stress-strain behavior of the material, this application establishes a cyclic elastoplastic constitutive model based on nonlinear kinematic hardening rate. In this model, the core differential equation describing the nonlinear cyclic behavior of the material, namely the master control equation, is shown in formula (2). The master control equation is the core part of the entire constitutive model and is used to capture the complex behaviors of the material such as viscoplastic deformation, cyclic hardening / softening and memory effect.

[0034] (2).

[0035] in, is the total strain rate tensor of the material to be tested; is the elastic strain rate tensor of the material to be tested; is the plastic strain rate tensor of the material to be tested; is the elastic strain tensor of the material to be tested; is the plastic strain tensor of the material to be tested; is the total strain tensor of the material to be tested.

[0036] Elastic strain tensor and the stress tensor The relationship between satisfies Hooke's law.

[0037] (3).

[0038] in, E and ν Represent elastic modulus and Poisson's ratio respectively; trσ represents stress tensor traces; I represents the second-order unit tensor.

[0039] The plastic flow criterion in the cyclic elastoplastic constitutive model can be defined by formula (4) and formula (5).

[0040] (4).

[0041] (5).

[0042] in, represents the cumulative inelastic strain rate; and They represent the deviator of the stress tensor and the deviator of the back stress tensor respectively. In tensor operations, the most common meaning of “:” in formula (5) is to represent the double contraction between two tensors, also known as “second-order contraction”, which is a high-order product operation.

[0043] The yield surface function in the cyclic elastoplastic constitutive model can be defined by formula (6).

[0044] (6).

[0045] in, represents the yield function; represents the initial yield stress.

[0046] The nonlinear kinematic hardening criterion in the cyclic elastoplastic constitutive model can be defined by formula (7).

[0047] (7).

[0048] in, represents the component ordinal number of the back stress tensor; and are material parameters that describe kinematic hardening. In the nonlinear kinematic hardening criterion, represents the back stress tensor No. components, which describe the kinematic hardening properties of the material, such as the Bauschinger effect. represents the back stress tensor With the evolution rate of plastic deformation, its significance lies in describing how the back stress is dynamically adjusted with the accumulation of plastic strain.

[0049] Specifically, formula (7) can also be expanded to formula (8).

[0050] (8).

[0051] in, , , , , , , , and Both are material parameters that describe kinematic hardening.

[0052] The damage model constructed in this application includes three aspects. The first is a creep damage model calculated by a method using failure inelastic strain energy density and inelastic strain energy density dissipation rate as main parameters. The second is a fatigue damage model calculated by a method using cyclic peak stress and equivalent plastic strain range as main parameters. The third is an oxidation damage model calculated by a method using oxidation kinetics and different oxygen concentration distributions in oxides as main parameters.

[0053] A method is established to determine the creep damage model of materials under multiaxial stress state, using the failure inelastic strain energy density and the inelastic strain energy density dissipation rate as the main parameters, as shown in formula (9).

[0054] (9).

[0055] in, is the creep damage value for each cycle; For each cycle of the finite element numerical calculation, it increases from 1 to The number of increments; Incremental step The creep damage value corresponding to the cycle after completion; is an incremental step The creep strain energy density dissipation rate after completion; is an incremental step The failure inelastic strain energy density after the end of the test; MDF is the multiaxial creep ductility factor; is the upper plateau of the inelastic strain energy density at failure.

[0056] (10).

[0057] (11).

[0058] in, is an incremental step Equivalent peak stress after completion; represents the equivalent mean stress per cycle; is the creep strain; and All are temperature-related material parameters; is a time-related parameter.

[0059] A fatigue damage model is established to determine the fatigue damage of materials under multiaxial stress state by using the method of cyclic peak stress and equivalent plastic strain range, as shown in formula (12).

[0060] (12).

[0061] in, The fatigue damage value for each week; Incremental step The fatigue damage value of the corresponding week after completion; Incremental step Equivalent plastic strain range after completion; is the peak stress during cyclic loading and unloading; and These are temperature-dependent material parameters.

[0062] An oxidation damage model is established to determine the oxidation damage of materials under multiaxial stress state by using different oxidation kinetics and oxygen concentration distribution in oxides, as shown in formula (13).

[0063] (13).

[0064] in, is the oxidative damage value for each week; Incremental step The oxidative damage value of the corresponding week after completion; is the radius of the cross section of the material to be tested; is the thickness of the oxidation affected zone of the material to be tested; is the thickness of the oxide on the material to be tested; is the parabolic rate constant; is the oxidation exposure time; The distance from the outer surface of the material to be tested to the outer surface of the material to be tested; is the oxidative damage index; is the maximum value of the oxidative damage index.

[0065] (14).

[0066] in, is a fitting parameter that reflects the degree of damage.

[0067] As a specific embodiment, Figure 2 As shown, the present application introduces a circular notch with a radius of 0.05 mm in the center of the creep-fatigue-oxidation specimen gauge section of the material to be tested, and the notch depths are 0.1 mm and 0.5 mm respectively. The finite element analysis software ABAQUS is used to establish a finite element model of the creep-fatigue-oxidation specimen gauge section with different notch depths. In order to improve efficiency and reduce calculation costs, a simplified two-dimensional symmetrical finite element model is selected, and the unit grid type of CPE4 is selected. The grid unit size away from the root of the notch is 0.1 mm × 0.1 mm. In order to more accurately reflect and calculate the material mechanical response at the root of the notch, the grid at the notch is refined, and its grid unit size is 0.005 mm × 0.005 mm. Symmetric boundary conditions are selected for the left boundary of the finite element model, and periodic displacement boundary conditions in the Y direction are applied to the upper boundary to simulate the displacement control conditions in the creep-fatigue-oxidation test, and fixed constraint boundary conditions in the Y direction are used for the lower boundary.

[0068] Step 2: Use the finite element solver to solve the simulation model and obtain the simulation results.

[0069] Specifically, the finite element analysis software ABAQUS solver is used to solve the finite element model of different geometric sizes and notch depths using the constitutive model and damage model written in the previous step to obtain simulation results, which include damage cumulative distribution cloud diagram, creep-fatigue-oxidation damage values ​​and the proportion of each damage. The creep damage value, fatigue damage value and oxidation damage value at different times of each week are extracted from the damage cumulative distribution cloud diagram, and the evolution law of the proportion of different types of damage under different holding times is analyzed, such as Figure 3 shown.

[0070] Step 3: Perform damage analysis and life prediction of the material to be tested based on the simulation results.

[0071] The step 3 is specifically divided into two parts: one is to calculate the damage value obtained according to the simulation model and use the linear damage accumulation criterion to predict the creep-fatigue-oxidation failure life; the other is to determine the material creep-fatigue-oxidation failure position according to the damage cumulative distribution cloud map of the simulation results.

[0072] According to the linear accumulation criterion, the creep-fatigue-oxidation failure life is determined. As shown in formula (15).

[0073] (15).

[0074] In conjunction with the accompanying drawings, the creep-fatigue-oxidation life data of notched specimens of P92 material with different notch depths at 600°C obtained from macroscopic tests are shown below, wherein the creep-fatigue-oxidation test is carried out on specimens with two different notch depths, the test temperature is 600°C, the loading mode is strain control, the strain ratio is -1, the total loaded strain range is 1.2%, the holding time is applied at the maximum tensile strain or the maximum compressive strain, the holding time selected for the specimen with a notch depth of 0.1mm is 60s, 300s, 600s, and 3600s, and the holding time selected for the specimen with a notch depth of 0.5mm is 60s, 600s, and 3600s. The specific implementation process of the life prediction method based on material damage analysis provided in the present application is explained.

[0075] 1) Establish simulation models with different notch forms, including two simulation models with different notch depths, such as Figure 2 As shown, Figure 2 a in the figure is a schematic diagram of the grid unit and boundary conditions of the simulation model with a notch depth of 0.1 mm; Figure 2 b is a schematic diagram of the grid unit and boundary conditions of the simulation model with a notch depth of 0.5 mm; Figure 2 Figure c is a local enlarged schematic diagram of the grid unit at the gap.

[0076] 2) Embed the constitutive model and damage model required for finite element analysis simulation calculation. In this embodiment, the parameter values ​​required for constructing the constitutive model and damage model of this application obtained by performing creep, fatigue and oxidation tests on P92 material at 600°C are shown in Table 1.

[0077] Table 1 Parameters of constitutive model and damage model 3) Extract the simulation results of the simulation model with different holding times for 0.1mm notch depth and 0.5mm notch depth, such as Figure 3 As shown, Figure 3 a in the figure is a schematic diagram of the damage ratio distribution when the notch depth is 0.1 mm; Figure 3 Figure b is a schematic diagram of the damage ratio distribution when the notch depth is 0.5 mm. It can be found that when the weekly holding time is no more than 600 s, fatigue damage is the main cause of material failure; the proportion of creep damage and oxidation damage increases monotonically with the increase of holding time. When the holding time reaches 300 s, in the finite element models of the two notch types, the proportion of creep damage exceeds one-fifth, and the proportion of oxidation damage also exceeds 5%; when the holding time increases to 3600 s, creep damage is the main cause of material failure, and its damage ratio exceeds half.

[0078] 4) Based on the creep, fatigue and oxidation damage values ​​calculated by the simulation model, the creep-fatigue-oxidation failure life is predicted using the linear damage accumulation criterion. Figure 4 The comparison results of creep-fatigue-oxidation life prediction obtained by finite element analysis and creep-fatigue-oxidation life obtained by test are shown, among which, Figure 4 a in the figure is the comparison result of notch depth of 0.1mm under different holding times. Figure 4 b is the comparison result of notch depth of 0.5 mm under different holding times. It can be seen that the creep-fatigue-oxidation life prediction results of the finite element analysis of this application are close to the life results obtained from the test, and both are within the double error band under different notch forms and different holding times. Therefore, the numerical simulation calculation method of this application has good accuracy and reliability.

[0079] 5) Extract the damage cumulative distribution cloud diagram from the simulation results, Figure 5 The damage cumulative distribution cloud diagram of the simulation model with a notch depth of 0.1 mm is given, where Figure 5 a in the figure is the damage cumulative distribution cloud diagram when the load holding time is 60s; Figure 5 b in the figure is the damage cumulative distribution cloud diagram when the load holding time is 300s; Figure 5 c in the figure is the damage cumulative distribution cloud diagram when the load holding time is 600s; Figure 5 Figure d is the damage cumulative distribution cloud diagram when the holding time is 3600s. It can be seen that when the holding time is short (no more than 600s), the creep-fatigue-oxidation failure position occurs at the root of the notch. When the holding time increases to 3600s, the creep-fatigue-oxidation failure position moves toward the inside of the notch. Figure 6 The damage cumulative distribution cloud diagram of the simulation model with a notch depth of 0.5 mm is given, where Figure 6 a in the figure is the damage cumulative distribution cloud diagram when the load holding time is 60s; Figure 6 b in the figure is the damage cumulative distribution cloud diagram when the load holding time is 600s; Figure 6c in the figure is the damage cumulative distribution cloud diagram with a holding time of 3600s. It can be found that the damage cumulative distribution cloud diagram of the simulation model with a notch depth of 0.5mm and the damage cumulative distribution cloud diagram of the simulation model with a notch depth of 0.1mm show similar characteristics, that is, the creep-fatigue-oxidation failure position with a short holding time occurs at the root of the notch, while the creep-fatigue-oxidation failure position with a long holding time is inside the notch.

[0080] In summary, this application obtains simulation results of material damage information at different positions of geometric discontinuous structures by establishing finite element models with different notch forms and embedding the constitutive model and damage model required for finite element analysis simulation calculations in the finite element model. The creep-fatigue-oxidation failure life and failure position are predicted based on the simulation results, effectively improving the accuracy of material damage analysis and life prediction.

[0081] In some embodiments, the present application also provides a computer program product, including a computer program, which implements the life prediction method based on material damage analysis when executed by a processor.

[0082] In some embodiments, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the life prediction method based on material damage analysis.

[0083] In some embodiments, the present application also provides a computer device, including a processor, a memory, an input / output interface (I / O for short), a communication interface, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the life prediction method based on material damage analysis.

[0084] Wherein, the processor, memory and input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Wherein, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store pending transactions. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the life prediction method based on material damage analysis is implemented.

[0085] It should be noted that the object information (including but not limited to object device information, object personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the object or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards.

[0086] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic variable memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0087] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above 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.

[0088] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A life prediction method based on material damage analysis, characterized in that: include: Constructing a simulation model of the material to be tested; the simulation model is obtained by writing a constitutive model and a damage model that simultaneously consider creep-fatigue-oxidation damage factors on the basis of a finite element model; The simulation model is solved by a finite element solver to obtain simulation results; the simulation results include a damage cumulative distribution cloud diagram and a creep-fatigue-oxidation damage value; The damage analysis and life prediction of the material to be tested are carried out based on the simulation results.

2. The life prediction method based on material damage analysis according to claim 1 is characterized in that: The construction of the simulation model of the material to be detected specifically includes: Finite element analysis software ABAQUS is used to establish a finite element model of the material to be tested with a notch; The constitutive model and damage model that simultaneously consider creep-fatigue-oxidation damage factors are written into the subroutine UVARM of the finite element model; the constitutive model includes a creep constitutive model and a cyclic elastic-plastic constitutive model; the damage model includes a creep damage model, a fatigue damage model and an oxidation damage model.

3. The life prediction method based on material damage analysis according to claim 2 is characterized in that: The creep constitutive model is ;in, is the equivalent creep rate of the material to be tested; is the equivalent creep strain of the material to be tested; is the equivalent deviatoric stress of the material to be tested; , and All are temperature-related material parameters; The cyclic elastoplastic constitutive model is ;in, is the total strain rate tensor of the material to be tested; is the elastic strain rate tensor of the material to be tested; is the plastic strain rate tensor of the material to be tested.

4. The life prediction method based on material damage analysis according to claim 2 is characterized in that: The creep damage model is ;in, is the creep damage value for each cycle; For each cycle of the finite element numerical calculation, it increases from 1 to The number of increments; Incremental step The creep damage value corresponding to the cycle after completion; is an incremental step The creep strain energy density dissipation rate after completion; is an incremental step The failure inelastic strain energy density after the end of the test; MDF is the multiaxial creep ductility factor; is the upper plateau of the inelastic strain energy density at failure.

5. The life prediction method based on material damage analysis according to claim 4 is characterized in that: The fatigue damage model is ;in, The fatigue damage value for each week; Incremental step The fatigue damage value of the corresponding week after completion; Incremental step Equivalent plastic strain range after completion; is the peak stress during cyclic loading and unloading; and These are temperature-dependent material parameters.

6. The life prediction method based on material damage analysis according to claim 5 is characterized in that: The oxidative damage model is ;in, is the oxidative damage value for each week; Incremental step The oxidative damage value of the corresponding week after completion; is the radius of the cross section of the material to be tested; is the thickness of the oxidation affected zone of the material to be tested; is the thickness of the oxide on the material to be tested; is the parabolic rate constant; is the oxidation exposure time; The distance from the outer surface of the material to be tested to the outer surface of the material to be tested; is the oxidative damage index; is the maximum value of the oxidative damage index.

7. The life prediction method based on material damage analysis according to claim 6 is characterized in that: The damage analysis and life prediction of the material to be tested based on the simulation results specifically include: Perform damage analysis on the material to be tested based on the damage cumulative distribution cloud diagram in the simulation results to determine the creep-fatigue-oxidation failure position of the material to be tested; According to the creep-fatigue-oxidation damage value in the simulation results, the creep-fatigue-oxidation failure life of the material to be tested is predicted using the linear damage accumulation criterion. .

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the life prediction method based on material damage analysis described in any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the life prediction method based on material damage analysis described in any one of claims 1 to 7 is implemented.

10. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the life prediction method based on material damage analysis as described in any one of claims 1 to 7.

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