A crystal plasticity inverse modeling and high-throughput prediction method and system

Abstract

The application belongs to the field of high-temperature deformation and fracture, and discloses a crystal plasticity reverse modeling and high-throughput prediction method and system, which comprises the following steps: observing the morphology and phase change behavior of a sample at a first preset temperature in situ; cooling the heated sample to obtain a sub-phase organization sample; reconstructing the morphology and orientation information of the parent phase of the sample; constructing a crystal plasticity RVE model; fitting to obtain high-temperature constitutive model parameters; obtaining crystallographic and crystal deformation information of the sample; performing an SEM in-situ high-temperature tensile test on the sample; analyzing the stress and strain evolution in the deformation process of the sample in situ by using DIC technology; and verifying the prediction accuracy. The application completes the modeling of the high-temperature austenite parent phase organization based on the room-temperature sub-phase organization reverse, and realizes the orientation analysis, texture analysis, deformation morphology analysis, stress and strain analysis and the like in the high-temperature deformation process by combining with the crystal plasticity simulation, so as to realize the in-situ high-throughput characterization of the high-temperature deformation.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of high-temperature deformation and fracture, and particularly relates to a crystal plasticity inverse modeling and high-throughput prediction method and system. BACKGROUND

[0002] In-service welding burn-through is essentially a high-temperature deformation and fracture problem under the coupling action of welding multi-physical fields and the pressure of the medium in the pipe. The dynamic failure process occurs in the high-temperature metal, and goes through dynamic evolution processes such as micro-defect initiation, micro-crack evolution and macro-crack propagation. At present, the mechanism of in-service welding burn-through is still lacking of systematic cognition, which seriously restricts the development of burn-through criterion. There are three major difficulties in the experimental study of the mechanism of in-service welding burn-through: (1) Burn-through occurs in a high-temperature process, which needs to overcome the difficulties of high-temperature research; (2) From high-temperature metal deformation to micro-defect initiation and evolution into burn-through, it is a dynamic process that needs to be observed in situ; (3) How to observe and analyze more characteristic parameters through a test system, such as comprehensive observation of crystal structure, orientation, stress and strain, deformation, defect evolution, etc., that is, high-throughput characterization problem. Therefore, solving the experimental characterization of the mechanism of in-service welding burn-through needs to solve the problems of high temperature, in-situ observation and high-throughput characterization.

[0003] In-service welding burn-through mainly occurs in the temperature range of 982℃-1570℃. The test temperature range of the laser confocal microscope in-situ tensile system is generally 50℃-1150℃, and the test temperature range of the scanning electron microscope in-situ high-temperature tensile system is generally 20℃-1200℃. Combined with high-temperature speckle preparation and DIC analysis, the above two in-situ characterization means can generally consider in-situ organization observation and strain analysis, but it is difficult to consider the influence of crystal orientation on high-temperature deformation and failure. The scanning electron microscope in-situ high-temperature tensile system can perform EBSD analysis by mounting an EBSD probe, but the temperature limit of the EBSD phosphor screen is about 800℃. Considering the safety and service life of the equipment, EBSD in-situ analysis is generally only allowed within 750℃. The existing in-situ test equipment mainly measures the temperature by welding or contacting a thermocouple probe on the back of the sample. The test temperature refers to the test temperature of the thermocouple probe, while the observation surface of the sample is the upper surface. It is still difficult to directly monitor the temperature change of the upper surface of the sample through the thermocouple probe. Due to the influence of heating system and sample heat dissipation, there is a certain temperature difference between the upper and lower surfaces of the sample. Therefore, it is difficult for high-temperature in-situ EBSD testing to make the upper surface of the sample completely undergo austenite phase transformation, and it is difficult to realize in-situ deformation and failure analysis in the austenite phase based on the in-situ high-temperature EBSD system.

[0004] Crystal plasticity finite element simulation technology can carry out deformation simulation based on actual crystal organization, and meanwhile, the method can also take into account information such as organization topography, crystal orientation and strain distribution, and is a high-throughput characterization and analysis technology. The actual crystal organization information required by the crystal plasticity simulation modeling needs to be obtained through the EBSD technology, but the existing EBSD characterization technology cannot carry out in-situ observation at a temperature of 750 DEG C and above, and cannot overcome the crystal plasticity RVE modeling problem of the real super-high-temperature organization. The high-temperature zone organization of the in-service welding feature has three main differences compared with the normal temperature organization: (1) different phase states, the BCC (body-centered cubic) structure of the steel matrix organization at high temperature is transformed into the FCC (face-centered cubic) structure of the austenite phase, and the deformation behaviors of the two are different; (2) different grain sizes, austenite organization grows at high temperature, and the austenite size is different at different temperatures; (3) different mechanical properties of the material at different temperatures. Therefore, the existing in-situ high-temperature EBSD system cannot obtain the organization information at a temperature of 750 DEG C and above. SUMMARY

[0005] In order to overcome the defects existing in the prior art, the purpose of the present application is to provide a crystal plasticity reverse modeling and high-throughput prediction method and system, which is based on the reverse modeling of the high-temperature austenite parent phase organization of the room-temperature sub-phase organization, and realizes the orientation analysis, texture analysis, deformation topography analysis, stress and strain analysis and the like in the high-temperature deformation process in combination with the crystal plasticity simulation, so as to realize the in-situ high-throughput characterization of the high-temperature deformation.

[0006] In order to achieve the above purpose, the present application provides the following technical scheme:

[0007] A crystal plasticity reverse modeling and high-throughput prediction method, comprising:

[0008] heating the sample to a first preset temperature, and in-situ observing the topography and phase change behavior of the sample at the first preset temperature;

[0009] cooling the heated sample to obtain a sub-phase organization sample;

[0010] based on the orientation relationship between the sub-phase and the parent phase, using the EBSD parent phase reconstruction technology to restore the topography and orientation information of the parent phase of the sample;

[0011] comparing the topography and phase change behavior of the sample at the first preset temperature with the topography and orientation information of the reconstructed parent phase of the sample, and constructing a crystal plasticity RVE model based on the topography and orientation information of the reconstructed parent phase of the sample;

[0012] setting a mechanical boundary condition, fitting to obtain high-temperature constitutive model parameters based on the high-temperature stress-strain curve and the phenomenological constitutive model of the sample;

[0013] Based on the crystal plasticity simulation technology, crystallographic and crystal deformation information of the sample is obtained;

[0014] The sample is subjected to SEM in-situ high-temperature tensile test, and the deformation morphology of the sample during deformation is observed and photographed;

[0015] Based on the deformation morphology of the sample during deformation, the stress and strain evolution of the sample during deformation is analyzed in-situ by using DIC technology;

[0016] The deformation, stress and strain evolution law of the sample is summarized, and the prediction accuracy of the law is verified.

[0017] Further, the sample is heated to a first preset temperature, and the morphology and phase change behavior of the sample at the first preset temperature are observed in-situ, including:

[0018] The sample is prepared into an in-situ high-temperature OM (optical microscope) tensile sample, and EBSD observation is performed on the in-situ high-temperature OM tensile sample to ensure that the resolution rate of the observation surface of the in-situ high-temperature OM sample is more than 95%;

[0019] The in-situ high-temperature OM tensile sample is subjected to in-situ high-temperature OM tensile test, and the in-situ high-temperature OM sample is heated to a first preset temperature at a speed not more than 13℃ / s and the observation surface is photographed;

[0020] The in-situ high-temperature OM tensile sample after heating is cooled at a speed greater than 30℃ / s to obtain a sub-phase organization sample, and the phase change behavior of the in-situ high-temperature OM tensile sample during cooling is observed.

[0021] Further, the sub-phase is martensite phase, and the parent phase is austenite phase.

[0022] Further, before the EBSD parent phase reconstruction technology is used to restore the morphology and orientation information of the sample parent phase, including:

[0023] The sub-phase organization sample is stored in vacuum.

[0024] Further, the mechanical boundary conditions are set, the high-temperature constitutive model parameters are fitted based on the high-temperature stress-strain curve of the sample and the phenomenological constitutive model, including:

[0025] Based on the open source DAMASK framework, the same external loading conditions as the in-situ high-temperature OM tensile test are set for the mechanical boundary conditions and periodic boundary conditions;

[0026] The sample is prepared into a high-temperature tensile sample and subjected to high-temperature tensile test to obtain the high-temperature stress-strain curve of the sample;

[0027] Based on the open source DAMASK framework, the mechanical behavior of the sample is described by using the phenomenological constitutive model, and the related parameters of the high temperature constitutive model are obtained based on the fitting of the high temperature stress-strain curve.

[0028] Further, based on the crystal plasticity simulation technology, the crystallographic and crystal deformation information of the sample is obtained, including:

[0029] Carrying out crystal plasticity simulation calculation and data processing on the sample;

[0030] The orientation, texture and stress-strain of the sample are obtained after the crystal plasticity simulation calculation;

[0031] The orientation, texture and stress-strain of the sample are visualized.

[0032] Further, before carrying out the SEM in-situ high temperature tensile test on the sample, including:

[0033] Using sample preparation to prepare an observation surface conforming to metallographic observation or EBSD observation;

[0034] Using 4% nitric acid alcohol to pre-etch the observation surface;

[0035] The microstructure morphology of the observation surface after high temperature phase transition is used as a high temperature speckle, and the high temperature speckle is used for DIC technology in-situ analysis.

[0036] Further, the sample is subjected to SEM in-situ high temperature tensile test, including:

[0037] The sample is heated to a second preset temperature, and the tensile test is directly started without heat preservation treatment, and the strain rate is controlled to be consistent with the in-situ high temperature OM tensile test;

[0038] Based on the SEM observation, the morphology change of the sample and the observation surface during the tensile process is photographed

[0039] Further, the prediction accuracy of the rule is verified, including:

[0040] The sample is subjected to a verification test, and the characteristic peak temperature of the verification test is controlled to be not higher than 750 DEG C;

[0041] The test temperature of the verification test is controlled to be between 982 DEG C and 1570 DEG C.

[0042] On the other hand, the application discloses a crystal plasticity reverse modeling and high-throughput prediction system, including:

[0043] In-situ observation unit: for heating the sample to a first preset temperature, and observing the morphology and phase change behavior of the sample at the first preset temperature in-situ;

[0044] Sub-phase microstructure sample acquisition unit: for cooling the heated sample to obtain a sub-phase microstructure sample;

[0045] Phase reconstruction unit: for reducing the morphology and orientation information of the sample phase based on the EBSD phase reconstruction technology based on the bit direction relationship between the sub-phase and the mother phase;

[0046] Crystal plastic RVE model construction unit: for comparing the morphology and phase change behavior of the sample at the first preset temperature with the morphology and orientation information of the reconstructed phase of the sample, and constructing a crystal plastic RVE model based on the morphology and orientation information of the reconstructed phase of the sample;

[0047] Phenomenological constitutive model parameter obtaining unit: for setting mechanical boundary conditions, and fitting to obtain phenomenological constitutive model parameters based on the high-temperature stress-strain curve of the sample and the phenomenological constitutive model;

[0048] Crystallographic and crystal deformation information obtaining unit: for obtaining the crystallographic and crystal deformation information of the sample based on the crystal plastic simulation technology;

[0049] SEM in-situ high-temperature tensile unit: for performing SEM in-situ high-temperature tensile test on the sample, observing and photographing the deformation morphology change of the sample during deformation;

[0050] DIC in-situ analysis unit: for in-situ analyzing the stress and strain evolution of the sample during deformation based on the deformation morphology change of the sample during deformation using DIC technology;

[0051] Precision verification unit: for summarizing the deformation, stress and strain evolution law of the sample, and verifying the prediction accuracy of the law.

[0052] Technical effects and advantages of the present application:

[0053] 1. The crystal plastic finite element simulation technology adopted by the present application can obtain conventional result types that can be obtained by EBSD, SEM, OM and in-situ DIC characterization means, and only needs to be simulated according to the real microstructure morphology and mechanical properties. The test cost of in-situ high-temperature EBSD and other characterization means is generally 2000 yuan / hour, and the cost of a test is about 10-20 thousand yuan, and there is a certain failure rate. The crystal plastic simulation technology can obtain more research results only with a small amount of inexpensive test data, and is a more efficient and inexpensive research means.

[0054] 2.The application combines the theory that the sub-phase organization after phase transition has a positional relationship with the high-temperature original austenite organization, and uses the EBSD parent phase reconstruction technology to restore the original austenite structure and orientation information at high temperature based on the sub-phase organization cooled to room temperature, realizes the reverse RVE modeling of the low-temperature sub-phase to the high-temperature parent phase, and then based on the high-temperature stress-strain curve and the phenomenological constitutive model, the high-temperature mechanical property parameters (high-temperature constitutive model parameters) of the austenite phase can be fitted and obtained, and then through crystal plasticity simulation, the orientation analysis, texture analysis, deformation morphology analysis, stress and strain analysis in the high-temperature deformation process can be realized, and the purpose of high-throughput characterization in situ is achieved, which makes up for the deficiency of in-situ test.

[0055] 3.The application is not only suitable for the research of high-temperature zone of in-service welding, but also provides a new idea for the research of deformation behavior of materials under high temperature or extreme conditions, and has an important role in helping to clarify the deformation mechanism of materials under extreme or high temperature conditions and related product research and development.

[0056] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present application. The objects and other advantages of the present application will be realized and attained by the structure particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 A flowchart of a crystal plasticity reverse modeling and high-throughput prediction method of the present application. DETAILED DESCRIPTION

[0058] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0059] As shown in the drawings, Figure 1 The present application provides a crystal plasticity reverse modeling and high-throughput prediction method, which comprises:

[0060] The sample is heated to a first preset temperature, and the morphology and phase change behavior of the sample at the first preset temperature are observed in situ;

[0061] The sample after heating is cooled to obtain a sub-phase organization sample;

[0062] Based on the positional relationship between the sub-phase and the parent phase, the EBSD parent phase reconstruction technology is used to restore the morphology and orientation information of the parent phase of the sample;

[0063] The morphology and phase change behavior of the sample at the first preset temperature are compared with the morphology and orientation information of the reconstructed parent phase of the sample, and a crystal plasticity RVE (representative volume unit) model is constructed based on the morphology and orientation information of the reconstructed parent phase of the sample;

[0064] The mechanical boundary condition is set, and the high-temperature constitutive model parameters are fitted based on the high-temperature stress-strain curve of the sample and the phenomenological constitutive model;

[0065] Based on the crystal plasticity simulation technology, the crystallographic and crystal deformation information of the sample is obtained;

[0066] The sample is subjected to an SEM in-situ high-temperature tensile test, and the deformation morphology of the sample during deformation is observed and photographed;

[0067] Based on the deformation morphology of the sample during deformation, the stress and strain evolution of the sample during deformation is analyzed in-situ by using the DIC technology;

[0068] The deformation, stress and strain evolution law of the sample is summarized, and the prediction accuracy of the law is verified.

[0069] In some embodiments of the present application, the sample is heated to a first preset temperature, and the morphology and phase change behavior of the sample at the first preset temperature are observed in-situ, including:

[0070] The sample is prepared into an in-situ high-temperature OM (optical microscope) tensile specimen, and EBSD observation is performed on the in-situ high-temperature OM tensile specimen to ensure that the resolution rate of the observation surface of the in-situ high-temperature OM specimen is more than 95%;

[0071] The in-situ high-temperature OM tensile specimen is subjected to an in-situ high-temperature OM tensile test, the in-situ high-temperature OM specimen is heated to a first preset temperature at a speed of not more than 13℃ / s (preferably the fastest heating speed allowed by the equipment), and a photograph of the observation surface is taken to simulate the material heating behavior during in-service welding;

[0072] The in-situ high-temperature OM tensile specimen after heating is cooled at a speed greater than 30℃ / s to obtain a sub-phase organization sample, and the phase change behavior of the in-situ high-temperature OM tensile specimen during cooling is observed.

[0073] It should be noted that rapid cooling can maximize the retention of the grain morphology of high-temperature austenite to obtain clearer original austenite grain boundaries, and can obtain a martensite structure, which has a good orientation relationship with the austenite parent phase, and can maximize the accuracy of subsequent reconstruction.

[0074] In some embodiments of the present application, the sub-phase is a martensite phase, and the parent phase is an austenite phase.

[0075] In some embodiments of the present application, before the EBSD parent phase reconstruction technology is used to restore the morphology and orientation information of the sample parent phase, the following steps are included:

[0076] The sub-phase organization sample is preserved in vacuum. The cooled sub-phase organization sample is preserved in a vacuum box and EBSD test is arranged as soon as possible, so that the observation surface after cooling still has a high EBSD resolution without re-sampling.

[0077] In some embodiments of the present application, the mechanical boundary condition is set, the high-temperature constitutive model parameters are fitted based on the high-temperature stress-strain curve of the sample and the phenomenological constitutive model, including:

[0078] Based on the open-source DAMASK framework, the mechanical boundary condition and the periodic boundary condition are set under the same external loading condition as the in-situ high-temperature tensile test;

[0079] The sample is prepared into a high-temperature tensile specimen and a high-temperature tensile test is performed to obtain the high-temperature stress-strain curve of the sample;

[0080] Based on the open-source DAMASK framework, the mechanical behavior of the sample is described by using the phenomenological constitutive model, and the related parameters of the high-temperature constitutive model are fitted based on the high-temperature stress-strain curve.

[0081] In some embodiments of the present application, based on the crystal plasticity simulation technology, the crystallographic and crystal deformation information of the sample is obtained, including:

[0082] The crystal plasticity simulation calculation and data processing are performed on the sample;

[0083] The orientation, texture and stress-strain of the sample are obtained after the crystal plasticity simulation calculation;

[0084] The orientation, texture and stress-strain of the sample are visualized.

[0085] In some embodiments of the present application, before the in-situ SEM high-temperature tensile test of the sample is performed, the following steps are included:

[0086] The observation surface of the sample is prepared to meet the metallographic observation or EBSD observation;

[0087] The observation surface is pre-etched with 4% nitric acid alcohol to obtain fine organization morphology;

[0088] The organization morphology of the observation surface after high-temperature phase transition is used as a high-temperature speckle, and the high-temperature speckle is used for in-situ analysis by DIC technology.

[0089] In some embodiments of the present application, the in-situ SEM high-temperature tensile test of the sample is performed, including:

[0090] The sample is heated to a second preset temperature, and a tensile test is directly started without a holding process, and the strain rate is controlled to be consistent with that of the in-situ high-temperature OM tensile test;

[0091] Based on SEM observation, the morphology changes of the microstructure and observation surface of the sample during the tensile process are photographed

[0092] In some embodiments of the present application, the prediction accuracy of the verification rule is verified, including:

[0093] The sample is subjected to a verification test, and the characteristic peak temperature of the verification test is controlled to be not higher than 750 DEG C, so that the test conditions and the boundary conditions of the crystal plasticity are as consistent as possible, and the reliability of the crystal plasticity method is verified to the maximum extent;

[0094] The test temperature of the verification test is controlled to be between 982 DEG C and 1570 DEG C, and is used to verify the reliability of the crystal plasticity reverse modeling and high-throughput prediction method in the high-temperature zone of the in-service welding characteristics.

[0095] In another aspect, the present application discloses a crystal plasticity reverse modeling and high-throughput prediction system, comprising:

[0096] An in-situ observation unit is used to heat the sample to a first preset temperature, and the morphology and phase change behavior of the sample at the first preset temperature are observed in-situ;

[0097] A sub-phase microstructure sample obtaining unit is used to cool the heated sample to obtain a sub-phase microstructure sample; a parent phase reconstruction unit is used to reconstruct the morphology and orientation information of the parent phase of the sample based on the orientation relationship between the sub-phase and the parent phase by using the EBSD parent phase reconstruction technology;

[0098] A crystal plasticity RVE model construction unit is used to compare the morphology and phase change behavior of the sample at the first preset temperature with the morphology and orientation information of the reconstructed parent phase of the sample, and construct a crystal plasticity RVE model based on the morphology and orientation information of the reconstructed parent phase of the sample;

[0099] A phenomenological constitutive model parameter obtaining unit is used to set mechanical boundary conditions, and obtain the phenomenological constitutive model parameters based on the high-temperature stress-strain curve of the sample and the phenomenological constitutive model;

[0100] A crystallography and crystal deformation information obtaining unit is used to obtain the crystallography and crystal deformation information of the sample based on the crystal plasticity simulation technology;

[0101] An SEM in-situ high-temperature tensile unit is used to perform an SEM in-situ high-temperature tensile test on the sample, and observe and photograph the deformation morphology changes of the microstructure and observation surface during the deformation process of the sample;

[0102] DIC in-situ analysis unit: for in-situ analysis of stress and strain evolution of the sample during deformation based on the deformation morphology change of the tissue and observation surface during sample deformation;

[0103] Accuracy verification unit: for summarizing the deformation, stress and strain evolution law of the sample, and verifying the prediction accuracy of the law.

[0104] In order to better illustrate the scheme, the following examples are provided.

[0105] Embodiment

[0106] This embodiment takes the deformation behavior research of X65 pipeline steel at 1150℃ as an example, and specifically describes the implementation method of the high-throughput prediction method of the in-service welding characteristic high-temperature zone crystal plasticity reverse modeling as follows.

[0107] Step 1: carry out in-situ high-temperature OM tensile test, heat the sample to the first preset temperature (1150℃), and observe the high-temperature morphology and phase change behavior in-situ, then obtain the sub-phase organization by rapid cooling, which includes the following steps:

[0108] (1) sample on X65 pipeline steel pipe and process into sample size required by OM in-situ high-temperature tensile test, since the sample thickness is very thin, the sample is pasted to the super flat sample block using glue for grinding and mechanical polishing operation, then the observation surface is vibrated and polished to remove the surface stress layer;

[0109] (2) use nano indentation or microhardness method to mark the observation position, so that the marked position can be found faster during subsequent observation;

[0110] (3) soak the super flat sample block with the sample in acetone solution for 6-12 hours, after the acetone dissolves the glue, take out the sample, remove a small amount of glue on the back surface with sandpaper, which needs to be sprayed with alcohol solution on the sample surface to protect the observation surface from oxidation, then ultrasonic cleaning and drying preservation in alcohol solution;

[0111] (4) install the sample on the OM high-temperature in-situ tensile test bench, heat to the first preset temperature (1150℃) at the fastest heating speed allowed by the equipment (~ 13℃ / s), do not perform heat preservation treatment after heating, to simulate the material heating behavior during in-service welding, the heating and cooling process of the sample is completed in ultra-pure argon to prevent the sample surface from being oxidized;

[0112] (5) after heating the sample to the first preset temperature (1150℃), use the automatic photographing system to take pictures, focus and other processes during shooting to ensure the clarity of the pictures;

[0113] (6) The sample is rapidly cooled at a rate greater than 30℃ / s to obtain the subphase structure. During the cooling process, the phase transformation behavior is observed, and the subphase structure after cooling is made as much as possible to ensure that it is martensitic. Rapid cooling can preserve the grain morphology of high-temperature austenite to the greatest extent and obtain clearer original austenite grain boundaries. Martensitic structure can also be obtained. The martensitic structure and the austenite parent phase have a good orientation relationship, which can ensure the accuracy of subsequent reconstruction to the greatest extent.

[0114] Step 2: Based on the orientation relationship between the child phase and the parent phase, the morphology and orientation information of the sample's parent phase are restored using EBSD parent phase reconstruction technology. This specifically includes the following steps:

[0115] (1) After completing the OM high temperature in-situ tensile test, the sample is removed and placed in the EBSD observation system to find the position of the nano-indentation or microhardness mark, and the corresponding position is found by referring to the picture taken by OM.

[0116] (2) Perform EBSD scanning on the observation position to ensure that the observation position of the sample still has a high resolution. If the resolution of the sample surface decreases significantly, precision polishing can also be used for polishing, but it is necessary to ensure that the morphology of the observation surface is not changed as much as possible.

[0117] (3) Compare the morphology and phase transformation behavior of the sample at the first preset temperature (1150℃) with the morphology and orientation information of the reconstructed parent phase of the sample. Under the premise of ensuring accuracy, construct a crystal plasticity RVE (representative volume unit) model based on the morphology and orientation information of the reconstructed parent phase of the sample.

[0118] Step 3: Construct a crystal plasticity RVE (Representative Volume Unit) model based on the morphology and orientation information of the parent phase reconstructed from the sample.

[0119] (1) Using EBSD parent phase reconstruction technology to match the corresponding orientation relationship, the morphology and orientation information of the high-temperature original austenite structure (parent phase) are reconstructed, and the results are exported as *.ctf files;

[0120] (2) Remove the zero resolution points in the *.ctf file and make the location of the zero resolution points match the surrounding crystal structure;

[0121] (3) Import the *.ctf file with zero resolution points removed into the open-source Dream.3D software to reconstruct the RVE model required for DAMASK crystal plasticity calculation.

[0122] Step 4: Set mechanical boundary conditions. Based on the high-temperature stress-strain curve and phenomenological constitutive model of the sample, fit and obtain the parameters of the high-temperature constitutive model. This includes the following steps:

[0123] (1) Based on the open source DAMASK framework, the same external loading conditions as the in-situ high temperature OM tensile test are adopted to apply mechanical boundary conditions and periodic boundary conditions. DAMASK uses a tensor method to apply load, and the load file is *.load file. The deformation rate tensor is expressed in the form of 3x3 tensor, as shown in the following formula,

[0124]

[0125] In the formula, F dot is the deformation gradient rate tensor.

[0126] (2) Set the strain rate and incremental step in *.load.

[0127] Step 5: Based on the crystal plasticity simulation technology, the crystallographic and crystal deformation information of the sample is obtained, including the following steps:

[0128] (1) Reasonably set the analysis steps to balance the calculation time, convergence and calculation accuracy;

[0129] (2) Perform crystal plasticity simulation calculation and data processing on the sample; after crystal plasticity simulation calculation, use the command to obtain the orientation, texture and stress-strain files of the sample

[0130] (3) Use visualization software to visualize the orientation, texture and stress-strain.

[0131] Step 6: SEM in-situ high temperature tensile sample preparation is carried out to prepare SEM in-situ high temperature tensile test;

[0132] (1) Process the sample into the required size, and use glue to paste it on the super flat experimental block to prepare the sample observation surface for metallographic observation or EBSD observation;

[0133] (2) Use 4% nitric acid alcohol to pre-etch the sample observation surface to obtain fine organization morphology;

[0134] (3) Soak the sample and super flat sample block in acetone solution for 6-12 hours, then take out the sample;

[0135] (4) The fine organization morphology after high temperature phase transition can be used as high temperature speckle to facilitate in-situ DIC analysis in the subsequent steps.

[0136] Step 7: SEM in-situ high temperature tensile test is carried out on the sample prepared in step 6 to observe and photograph the deformation morphology of the sample during deformation, including the following steps:

[0137] (1) the sample is heated to a second preset temperature at the fastest heating speed allowed by the equipment to simulate the material temperature rising behavior during in-service welding, and the heating and cooling processes are completed in an argon protective atmosphere to prevent the sample surface from being oxidized;

[0138] (2) after heating to the second preset temperature, the tensile test is directly started without heat preservation treatment, and the strain rate is consistent with that of the in-situ high-temperature OM tensile test;

[0139] (3) during the tensile process, if SEM observation and photographing operation are needed, the tensile process needs to be stopped, and the sample needs to be locked, and the photographing is performed after the time-stress curve of the sample is stable;

[0140] (4) based on the SEM observation, the deformation process of the sample and the deformation morphology change of the observation surface are photographed.

[0141] Step 8: based on the sample deformation process and the deformation morphology change of the observation surface obtained in step 7, the stress and strain evolution of the sample during the deformation process are analyzed in-situ by using the DIC technology, and the specific steps are as follows:

[0142] (1) the initial structure without deformation is selected as the reference photo;

[0143] (2) based on the reference photo, the reference photo and the previous photo are taken as the reference respectively, and the mesoscopic stress and strain cloud diagram during the deformation process is calculated.

[0144] Step 9: the deformation, stress and strain evolution law of the sample is summarized, and the prediction accuracy of the law is verified, and the specific steps include the following steps:

[0145] (1) the sample is subjected to a verification test, and the characteristic peak temperature of the verification test is controlled to be not higher than 750 DEG C, so that the test conditions and the boundary conditions of the crystal plasticity are as consistent as possible, and the reliability of the crystal plasticity method is verified to the maximum extent;

[0146] (2) the test temperature of the verification test is controlled to be between 982 DEG C and 1570 DEG C, so as to verify the reliability of the crystal plasticity reverse modeling and high-throughput prediction method in the characteristic high temperature zone of in-service welding.

[0147] Finally, it should be pointed out that the above only describes the preferred embodiments of the present application and is not used to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, for those skilled in the art, the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced, and any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for inverse modeling and high-throughput prediction of crystal plasticity, characterized in that, include: The sample was heated to a first preset temperature, and its morphology and phase transition behavior at the first preset temperature were observed in situ. The heated sample was cooled to obtain a subphase tissue sample; Based on the orientation relationship between the child phase and the parent phase, the morphology and orientation information of the parent phase of the sample are restored using the EBSD parent phase reconstruction technology; The morphology and phase transition behavior of the sample at the first preset temperature are compared with the morphology and orientation information of the reconstructed parent phase of the sample. Based on the morphology and orientation information of the reconstructed parent phase of the sample, a crystal plasticity RVE model is constructed. Mechanical boundary conditions are set, and the high-temperature constitutive model parameters are obtained by fitting based on the high-temperature stress-strain curve and phenomenological constitutive model of the sample. Based on crystal plasticity simulation technology, the crystallographic and crystal deformation information of the sample is obtained, including: Crystal plasticity simulation calculations and data processing were performed on the sample. The orientation, texture, and stress-strain of the sample were obtained after the crystal plasticity simulation calculation. The orientation, texture, and stress-strain of the sample are visualized. The sample was subjected to an in-situ high-temperature tensile test using SEM, and the changes in the microstructure and deformation morphology of the observation surface during the deformation process were observed and photographed. Based on the changes in the deformation morphology of the microstructure and observation surface during the deformation process of the sample, the stress and strain evolution during the deformation process of the sample was analyzed in situ using DIC technology. The deformation, stress, and strain evolution patterns of the samples were summarized, and the predictive accuracy of these patterns was verified.

2. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 1, characterized in that, The method of heating the sample to a first preset temperature and observing the morphology and phase transition behavior of the sample at the first preset temperature in situ includes: The sample was prepared into an in-situ high-temperature OM tensile specimen, and the in-situ high-temperature OM tensile specimen was observed by EBSD to ensure that the resolution of the observation surface of the in-situ high-temperature OM specimen was above 95%. An in-situ high-temperature OM tensile test was performed on the in-situ high-temperature OM tensile specimen. The in-situ high-temperature OM specimen was heated to a first preset temperature at a rate not exceeding 13℃ / s and an observation surface photograph was taken. The heated in-situ high-temperature OM tensile specimen was cooled at a rate greater than 30°C / s to obtain a subphase microstructure sample, and the phase transformation behavior of the in-situ high-temperature OM tensile specimen during the cooling process was observed.

3. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 1, characterized in that, The daughter phase is martensite, and the mother phase is austenite.

4. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 1, characterized in that, Before using EBSD parent phase reconstruction technology to restore the morphology and orientation information of the sample parent phase, the following steps are included: The subphase tissue sample was preserved under vacuum.

5. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 2, characterized in that, The aforementioned setting of mechanical boundary conditions, based on the high-temperature stress-strain curve and phenomenological constitutive model of the sample, and fitting to obtain high-temperature constitutive model parameters, includes: Based on the open-source DAMASK framework, mechanical boundary conditions and periodic boundary conditions are set using the same external loading conditions as in-situ high-temperature OM tensile tests. The sample was prepared into a high-temperature tensile specimen and subjected to a high-temperature tensile test to obtain the high-temperature stress-strain curve of the sample. Based on the open-source DAMASK framework, a phenomenological constitutive model is used to describe the mechanical behavior of the sample, and the relevant parameters of the high-temperature constitutive model are obtained by fitting the high-temperature stress-strain curve.

6. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 1, characterized in that, Before performing the SEM in-situ high-temperature tensile test on the sample, the following steps are included: Utilize sample preparation to create observation surfaces suitable for metallographic or EBSD observation; The observation surface was pre-etched using 4% nitric acid alcohol. The microstructure after the high-temperature phase transition on the observed surface is used as high-temperature speckle, which is then used for in-situ analysis using the DIC technique.

7. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 2, characterized in that, The aforementioned in-situ high-temperature tensile test of the sample using SEM includes: The sample is heated to a second preset temperature, and the tensile test is started directly without heat preservation treatment, and the strain rate is controlled to be consistent with the in-situ high-temperature OM tensile test. The morphological changes of the tissue and the observation surface during the stretching process of the sample were observed and photographed using SEM.

8. The method for inverse modeling and high-throughput prediction of crystal plasticity according to claim 1, characterized in that, The verification of the prediction accuracy of the stated pattern includes: The sample was subjected to a verification test, and the characteristic peak temperature of the verification test was controlled to be no higher than 750℃; The test temperature for the control verification test is between 982℃ and 1570℃.

9. A crystal plasticity inverse modeling and high-throughput prediction system, characterized in that, include: In-situ observation unit: used to heat the sample to a first preset temperature and observe the morphology and phase transition behavior of the sample at the first preset temperature in situ; Subphase tissue sample acquisition unit: used to cool the heated sample to obtain a subphase tissue sample; Parent phase reconstruction unit: used to restore the morphology and orientation information of the sample parent phase based on the orientation relationship between the child phase and the parent phase using EBSD parent phase reconstruction technology; Crystal plasticity RVE model construction unit: used to compare the morphology and phase transformation behavior of the sample at a first preset temperature with the morphology and orientation information of the reconstructed parent phase of the sample, and construct a crystal plasticity RVE model based on the morphology and orientation information of the reconstructed parent phase of the sample; Phenomenological constitutive model parameter acquisition unit: used to set mechanical boundary conditions, and to obtain phenomenological constitutive model parameters based on the high-temperature stress-strain curve and phenomenological constitutive model of the sample. Crystallography and Crystal Deformation Information Acquisition Unit: Used to obtain crystallography and crystal deformation information of the sample based on crystal plasticity simulation technology, including: Crystal plasticity simulation calculations and data processing were performed on the sample. The orientation, texture, and stress-strain of the sample were obtained after the crystal plasticity simulation calculation. The orientation, texture, and stress-strain of the sample are visualized. SEM in-situ high-temperature tensile unit: used to perform SEM in-situ high-temperature tensile tests on the sample, observe and photograph the changes in the deformation morphology of the sample and the observation surface during the deformation process; DIC in-situ analysis unit: used to analyze the stress and strain evolution of the sample in situ during the deformation process based on the changes in the deformation morphology of the tissue and observation surface during the deformation process of the sample using DIC technology; Accuracy verification unit: used to summarize the deformation, stress and strain evolution laws of the sample and verify the prediction accuracy of the laws.

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