29 results about "Material Crack" patented technology

The invention relates to the technical field of new materials, in particular to an admixture as well as a preparation method and application thereof. The admixture is prepared from the following components in parts by mass: 1.0 to 5.0 parts of a complexing agent, 1.5 to 8.0 parts of a calcium ion compensating agent, 1.0 to 8.0 parts of a crystallization accelerant, 3.0 to 10.0 parts of a slow release agent, 5.0 to 15.0 parts of an active mineral admixture, 15.0 to 28.5 parts of an expanding agent, 20.0 to 40.0 parts of Portland cement and 10.0 to 20.0 parts of quartz sand. The admixture can realize self-repairing of cement-based material cracks in humid and water seepage environments, has the functions of improving matrix strength and waterproof performance, reducing hydration heat, delaying temperature peak appearance and the like, and is wide in application range.

The present application belongs to the technical field of wind power generation, and specifically relates to a wind power tower material crack propagation prediction method and system, which is suitable for fatigue life evaluation of large supporting structures in the wind energy industry. The method comprises: deploying a multi-source heterogeneous sensor network to collect strain, acoustic emission and environmental load data; constructing a digital twin high-fidelity finite element submodel to obtain a dynamic stress intensity factor; constructing a deep neural network, embedding the Paris law of fracture mechanics in the form of residual into the loss function to form a physical information neural network, and realizing crack propagation rate prediction; using the extended finite element method combined with the level set function and the maximum circumferential stress criterion to dynamically track the three-dimensional space expansion path of the crack; combining Monte Carlo simulation and recursive Bayesian update to evaluate the remaining life and trigger graded early warning. The present application solves the problems of insufficient fusion of physical mechanisms and data-driven in the prior art, low prediction accuracy under small samples, and lack of crack space path tracking.

The application discloses a kind of weak magnetic signal characteristic research methods for ferromagnetic material, comprising: according to the magnetomechanics model in the step of establishing magnetomechanics model, the verification of magnetomechanics model is carried out by pipeline weld model, pipeline weld crack model and pipeline base material crack model in the step of initial pressure simulation calculation, then according to the magnetomechanics model after verification, the step of pressurization simulation calculation is carried out, the stress damage degree of magnetomechanics model of pipeline weld model, pipeline weld crack model and pipeline base material crack model is obtained, based on the step of pressurization simulation calculation, by gradient energy factor calculation step and introduction same rate growth rate step, the stress damage degree of pipeline weld model, pipeline weld crack model and pipeline base material crack model is realized quantitative reflection.This application establishes magnetomechanics model, and introduces gradient energy factor, better reflects the stress damage of pipeline weld model, pipeline weld crack model and pipeline base material crack model.

This invention provides a method for determining the critical state of cracks in viscoelastic materials under dynamic interaction of cracking and healing. Specifically, it involves: establishing a geometric model of the energy change region under dynamic interaction of cracking and healing; constructing energy dissipation and recovery strain energy models for the apparent and actual configurations of the viscoelastic material sample during the loading stage; determining the size and net increase in damage density of the viscoelastic material sample under dynamic interaction of cracking and healing; constructing a model relating the recovery strain energy and the net increase in damage density during the healing stage; using the sum of the increase in volume free energy due to viscoelastic failure volume recovery and the decrease in surface energy due to crack healing as the total free energy increment; calculating the rate of change of the free energy increment; and determining the critical state of the crack based on this method. This invention provides a basis for determining the critical transition of crack instability propagation in materials with viscoelastic and healing properties.

The invention relates to the technical field of material crack propagation testing, in particular to an SEB sample crack propagation testing method in a corrosive medium environment, which comprises the following steps: repeatedly carrying out a crack propagation test in a conventional air and room temperature environment, and deducing a regularized crack length alpha LVDT = gt according to a synchronous measurement result of a COD gauge and an LVDT sensor; according to the basic mapping relation of alpha < LVDT > and alpha < COD >, further comparing the mapping relation with actual measurement data of a COD gauge to obtain corrected alpha < LVDT > = gt; then, carrying out a crack propagation test in a high-temperature corrosion environment, and according to the corrected alpha LVDT = gt; and calculating the crack length a according to the mapping relation of alpha COD. Through the steps, the purpose of carrying out crack propagation test on the three-point bending SEB sample in a corrosive medium environment is achieved, and meanwhile, the accuracy of a test result is ensured.

The application relates to the technical field of mechanical testing devices, and particularly discloses a multi-scale in-situ monitoring device applied to material crack propagation and a testing method thereof. The device comprises a DCPD testing part, a DIC testing part and an electric control cabinet; the DCPD testing part comprises a fixed frame, a room temperature clamping device, a force loading system and a data acquisition system; and the DIC testing part comprises a DIC camera. Through the cooperation of the DCPD and the DIC, real-time monitoring of a macroscopic crack propagation rate and in-situ analysis of a microscopic crack tip stress and strain field distribution are realized, so that cross-scale material damage evolution information is obtained. The device has the advantages of computer full-digital control, high measurement precision, multi-dimensional synchronous data acquisition and the like, and is particularly suitable for high-precision, multi-scale material damage detection and failure mechanism research in an air environment.

The invention discloses a design method of a dense-phase carbon dioxide pipeline composite material crack stopper, which comprises the following steps: S1, selecting a sample steel pipe, and determining a steady-state expansion crack tip opening angle CTOA of a crack in the steel pipe; s2, the crack arrest critical CTOAc of the steel pipe is determined; s3, establishing a finite element model: performing grid division on the pipeline by adopting five layers of entity units, wherein a cohesion unit is adopted as a crack propagation path; s4, establishing a pressure attenuation model; s5, loading pressure by a two-step method, and simulating the pressure behind the tip of the crack; s6, determining cohesion parameters, and taking the cohesion parameters as finite element model parameters; s7, determining a crack arrestor model, setting a crack arrestor criterion, and performing finite element calculation to output CTOAa; and S8, determining a crack arrest criterion of the crack arrestor, and completing the design of the crack arrestor. According to the design method of the composite material crack arrestor for the dense-phase carbon dioxide pipeline, the problem that the crack cannot be stopped in time after the dense-phase carbon dioxide pipeline with the small caliber of OD508 or below is cracked is solved.

The invention provides a cyclic loading-multi-stage intermittent asphalt material fatigue crack critical healing point testing method, and aims to test a material self-healing failure critical point by gradually increasing the fatigue damage degree of an asphalt material. The test method comprises three stages: a lossless load cyclic loading stage, a lossy load cyclic loading stage and a multi-stage intermittent and lossless loading stage. Besides, the damage density variable quantity of the asphalt material after the fatigue crack is healed is used as an evaluation index of the healing critical point, the physical meaning of the damage density variable quantity is the crack area reduction proportion of the asphalt material before and after the intermittent fatigue crack is healed, and the smaller the numerical value is, the closer the material critical healing point is under the current damage degree. The index overcomes the limitation of experience-dependent macro-performance indirect evaluation in the prior art, and provides technical support for healing ability evaluation and material crack resistance optimization design of asphalt materials.

The application discloses a brittle material crack propagation prediction method, comprising the following steps: a brittle material entity model is discretized into a series of space material points through space grid multi-level division; parameters of the brittle material are acquired and taken as input of a prediction model; a prototype micro-brittle model constitutive relation is constructed based on space coordinates, the size of a near-field domain and a dual domain is set, and a key force action range is determined; initial boundary conditions are determined, and an external force is applied by using a progressive loading; physical and mechanical information such as material point position, velocity, acceleration and the like is updated in real time by using an explicit iteration method, and a critical elongation bond breaking criterion is used to describe damage cracking; displacement results and damage results at different times are output, the position and time of damage and cracking are recorded, and crack propagation paths at different times are acquired. The application solves the false stress wave problem caused by variable near-field domain size, and can effectively predict and analyze the mechanical behavior and damage problem of the brittle material under the action of a load.

This invention discloses a method for assessing the cracking risk of metallic materials, relating to the field of additive manufacturing of metallic materials, to solve the problem of difficulty in assessing the impact of structural complexity and dimensional differences on the cracking risk of materials when processing complex structure printing tasks. The assessment method includes: acquiring length data of typical samples of the metal to be assessed, where typical samples are thin-walled structures and large-size structures; calculating a first average rate for the thin-walled structure in a first time period and a second average rate in a second time period, and a third average rate for the large-size structure in the first time period and a fourth average rate in the second time period, based on the length data; calculating a first weighted average rate in the first time period based on the first and third average rates; calculating a second weighted average rate in the second time period based on the second and fourth average rates; and performing a risk assessment of the metal to be assessed based on the first and second weighted average rates.

A rapid real-time visualization system for a crack initiation process of a concrete component includes a pressure test machine, a fluorescent solution spraying device, an ultraviolet lamp group, a visible light imaging device group and a computer control system. Before the concrete component cracks, a surface of the concrete component is coated with a fluorescent solution retention layer to separate the sprayed fluorescent excitation solution from the concrete component, making the fluorescent excitation solution adhere to the fluorescent solution retention layer for a long time to mark cracks at any position in real time. The rapid real-time visualization system is used to achieve visualization of the crack initiation process, especially an early stage thereof. The rapid real-time visualization system and method can be used to study patterns of microcrack mutual traction development and aggregation into groups when concrete materials crack at any position or multiple points at a component scale.

The utility model discloses a metal material deformation crack detection device, which comprises a mounting frame, a supporting assembly convenient for supporting a metal material is arranged on the lower side wall of the mounting frame, transverse electric push rods are fixedly arranged on the left side and the right side of the mounting frame, and mounting plates are fixedly arranged at the output ends of the transverse electric push rods. The transverse electric push rod drives the fixing base to move through the mounting plate, the fixing base drives the rotating shaft to move through the bearing, the clamping plate clamps the metal material, then the driving assembly drives the rotating shaft to drive the clamping plate to rotate, the clamping plate drives the metal material to rotate, and therefore the metal material is turned over. The two sides of the metal material can be detected only by rotating the rotating shaft, a large amount of time is prevented from being wasted when the metal material is taken down and turned over, the situation that the metal material is too large in size and needs to be turned over with the help of an external lifting appliance is avoided, and metal material crack detection is more convenient.

The application discloses a cement material crack microbial repair effect evaluation method and belongs to the field of cement material repair effect performance evaluation. The repair effect evaluation device comprises a mechanical evaluation system, a penetration pressure measurement evaluation system and an internal structure analysis evaluation system. The mechanical evaluation system comprises an axial pressure equipment and a confining pressure equipment. The penetration pressure measurement evaluation system comprises a liquid injection pipe, a liquid discharge pipe and a sensor. The liquid source comprises a water source and a calcium source. The internal structure analysis evaluation system comprises a 360-degree rotatable acoustic probe arranged at both ends of the sample. The application aims to avoid evaluating the microbial repair effect from a single aspect, break through the single angle and limitation of the traditional identification "real breakthrough pressure" method, more clearly observe and evaluate the sample crack repair effect, reveal the growth, development, distribution position and deposition form of the microorganism in the crack, and avoid complicated and complex operations to realize full-time continuous monitoring.

This invention provides a method and system for quantitatively detecting material crack depth based on thermal gradient vector field, belonging to the field of nondestructive testing technology. The invention proposes a quantitative detection scheme of unilateral heat flow excitation + orthogonal gradient scanning: First, a unilateral high-temperature boundary is constructed using a portable chemical self-heating pack and insulating material, forcing the heat flow to transversely cross the crack, forming a significant temperature step; second, infrared thermographic sequences of the cooling process are acquired to construct a two-dimensional thermal potential energy field and calculate the global gradient vector field; morphological algorithms are used to extract the crack topological skeleton, and virtual rays are emitted along the local orthogonal detection direction determined by the local thermal gradient direction at the skeleton nodes. Adaptive orthogonal integration is performed to extract multidimensional spatial features under multiple time series, which are then input into a supervised learning regression model to invert the physical depth of the crack. This invention effectively eliminates the geometric projection error caused by crack curvature, and features high computational accuracy and strong anti-interference ability, making it suitable for large-scale rapid detection in engineering sites.

The invention relates to the technical field of structure detection, in particular to a damage factor fused material crack prediction method, system, equipment and medium, firstly, multi-path and multi-frequency ultrasonic guided wave signals of a composite material structure to be detected are obtained, and multiple damage factors in a time domain and a frequency domain are extracted respectively; performing weighted fusion on the multiple damage factors by using a principal component analysis method to obtain a comprehensive damage factor; constructing a multi-task Gaussian process regression model adopting a joint kernel function, wherein the joint kernel function comprises an input kernel for representing the similarity of input features and a task kernel for representing the similarity between tasks; and finally, inputting the comprehensive damage factor into the model, and outputting a crack length predicted value and a confidence interval thereof. According to the method, through feature fusion and multi-task joint modeling, the problem of poor generalization ability under small sample and cross-regional working conditions in the prior art is effectively solved, high-precision prediction and uncertainty quantification of crack propagation are realized, and the reliability of structural health monitoring is improved.

The application discloses a kind of based on bacillus pasteurii mineralization deposition crack self-repair cement-based material and preparation method, including cement base material, premix one and premix two, the premix one includes urease-producing bacteria and carrier that have adsorbed calcium ion, and the premix two includes urease-producing bacteria and carrier that are not adsorbed calcium ion.The diatomite of the microorganism of the present application is divided into two parts, one part is diatomite load not in advance adsorbed calcium ion microorganism, and another part is diatomite load in advance adsorbed calcium ion microorganism.Therefore, both can ensure that cement-based material crack is repaired in time after cracking, and the durability of cement-based material after repair can be improved.The crack self-repair renewable cement-based material based on bacillus pasteurii mineralization deposition prepared by the present application is a kind of renewable cement-based material with crack self-diagnosis and self-repair, green and environmental protection, meets the current economic society to the green, environmental protection and intelligent requirements of building material.

The utility model discloses a novel composite thermal insulation pipeline which comprises a pipe body, the pipe body is composed of a protective layer and a liner pipe, the liner pipe comprises an inner pipe, a composite thermal insulation layer is arranged on the outer surface of the inner pipe, an outer layer is arranged on the outer surface of the composite thermal insulation layer, and a damping mechanism is arranged between the pipe body and the liner pipe and used for damping the liner pipe. The top of the liner pipe is communicated with a branch pipe, a top block is fixedly mounted at the top of the branch pipe, a piston is slidably mounted in the branch pipe, a second spring is fixedly mounted between the upper surface of the piston and the lower surface of the top block, and a pressure relief hole located above the piston is formed in the surface of the branch pipe. The heat preservation pipeline can be effectively buffered and damped, the situation that a heat preservation material cracks or falls off due to fatigue stress caused by continuous vibration is avoided, pressure in the heat preservation pipeline can be released in time through arrangement of a branch pipe, an ejector block, a piston, a second spring, a pressure relief hole and the like, the phenomenon that a lining pipe is damaged by large pressure, and the phenomenon of cracking or pipe explosion occurs is avoided, and the service life of the heat preservation pipeline is prolonged. And the safety is greatly improved.

The invention relates to the field of stone repairing, and particularly discloses a stone soaking pool crack repairing process. A stone soaking pool crack repairing technology comprises the following steps that S1, a to-be-repaired crack of a soaking pool is deeply cleaned, and it is ensured that the to-be-repaired crack is dry and clean; s2, a U-shaped or V-shaped groove is formed in the crack trend, and repairing glue is injected into the groove; s3, after the repairing adhesive is cured, grinding and polishing are conducted, a nanometer protective agent is sprayed to the surface of the repairing adhesive which is ground to be flat, and natural drying is conducted; the repairing adhesive comprises the following raw materials in parts by weight: a nano lithium silicate hybrid polymer, Portland cement, sodium silicate, porous carbon nanofibers, stone powder, glutinous rice glue, silica fume, a defoaming agent and water. According to the repairing adhesive disclosed by the invention, the bonding strength of stone cracks is greatly improved, so that a repaired stone bubble pool has relatively good anti-seepage capability and cold and hot cycle stress cracking resistance.

The invention discloses an engineering cement-based composite material crack intelligent detection and analysis method, and belongs to the technical field of civil engineering material damage identification, and the method comprises the steps: constructing an image data set of an engineering cement-based composite material uniaxial tensile test piece, designing a SegB2-Unet semantic segmentation model, fusing a Segformer-B2 encoder and an improved U-Net decoder, and carrying out the segmentation of the SegB2-Unet semantic segmentation model. Realizing crack feature extraction of the image data set through a multi-scale feature fusion module and an attention mechanism; carrying out data enhancement by adopting a CycleGAN generative adversarial network, and generating a synthetic crack image of a complex illumination scene; performing crack semantic segmentation on the input image based on a SegB2-Unet model to obtain a binary segmentation mask; and performing morphological skeletonization and bifurcation point detection processing on the segmentation mask, and extracting global feature parameters and local feature parameters of the crack. According to the method, high-precision identification of the microcracks of the engineering cement-based composite material is realized.

The invention discloses an anti-cracking high-strength forming process for a nut column of a charging pile circuit board, and relates to the field of metal material modification processing, and the anti-cracking high-strength forming process comprises the following steps: S1, material preparation: selecting a modified SWRCH22A alloy material, and carrying out trademark, packaging, batch number, chemical composition and RoHS conformity inspection on the modified SWRCH22A alloy material until the modified SWRCH22A alloy material is qualified; s2, cold heading forming is conducted, specifically, after the modified SWRCH22A alloy material is preheated, a nut column blank is formed through a numerical control cold heading machine; s3, thread rolling machining is conducted, specifically, thread rolling treatment is conducted on the blank, burrs are removed in the machining process, and it is guaranteed that the thread size meets the design requirement; and S4, segmented heat treatment is conducted, specifically, quenching treatment and tempering treatment are conducted in sequence, so that the workpiece meets the preset hardness requirement. Through targeted optimization of the material formula and the whole-flow process design, the problems of insufficient material cracking resistance, poor processing precision, poor performance stability, insufficient corrosion resistance, low product percent of pass and the like in an existing charging pile circuit board nut column forming process are effectively solved.

The invention relates to the technical field of mechanical test devices, and particularly discloses a multi-scale in-situ monitoring device applied to material crack propagation and a test method of the multi-scale in-situ monitoring device. The equipment comprises a DCPD test part, a DIC test part and an electric control cabinet, the DCPD test part comprises a fixed frame, a room temperature clamping device, a force loading system and a data acquisition system; the DIC test unit includes a DIC camera. Through cooperative combination of DCPD and DIC, real-time monitoring of macroscopic crack growth rate and in-situ analysis of microcosmic crack tip stress-strain field distribution are realized, so that cross-scale material damage evolution information is obtained. The equipment has the advantages of computer full-digital control, high measurement precision, multi-dimensional synchronous acquisition of data and the like, and is particularly suitable for high-precision and multi-scale material damage detection and failure mechanism research in an air environment.

A kind of quick screening method of potting material crack resistance belongs to the technical field of material performance and reliability evaluation, and the method comprises the following steps: step 1: preparing sample, preparing a screening appliance, which has pouring groove, and the middle part of the bottom surface of pouring groove is vertically provided with embedded part of rigid structure, embedded part has at least one sharp corner structure, the screening appliance is preheated to predetermined temperature, the liquid potting material to be evaluated is poured into pouring groove, and the inner side wall of pouring groove and potting material are mutually adhered;Step 2: solidification;Step 3: induce cracking test, after solidification is completed, at least one rapid cooling treatment is carried out on screening appliance and sample;Step 4: result observation and evaluation, whether radial radial crack is generated at sharp corner of embedded part is observed by visual or microscopic observation, and "cracking" or "not cracking" is used as the most direct screening basis.The scheme can more quickly, low cost and accurately screen the potting material of I type cracking failure.

This application discloses a multi-field coupled monitoring system and method for the self-healing process of cracks in barrier materials, relating to the field of seepage-proof barrier materials. A hydraulic device is located at the bottom of the pressure chamber's inner cavity, and a reaction frame is located at the top of the pressure chamber. A temperature control coil is installed on the inner wall of the pressure chamber, connected to an external high-low temperature circulating bath via a temperature control circulation pipeline to regulate the sample temperature and conduct freeze-thaw cycle tests. The pressure chamber is connected via pipeline to an external storage tank containing seepage solution, which is pumped into the sample by a constant flow injection pump. Pressure sensors and flow meters monitor the seepage parameters inside the sample. Several ultrasonic transducers are distributed on the outer wall of the pressure chamber to monitor changes in the internal crack structure of the sample. Fiber optic sensors are pre-embedded on both sides of the crack to monitor strain changes near the crack. This scheme can conduct experiments under multi-field coupled conditions such as loading, seepage, and temperature cycling, achieving comprehensive monitoring of the crack seepage-reaction-structural evolution process.

The present invention relates to the technical field of electronic components, and specifically discloses a magnetic core material, a preparation method therefor, and a coated inductor. The magnetic core material, which is used in a coated inductor, has a cracking resistance coefficient Z, wherein the cracking resistance coefficient Z = 0.1 x - 0.5 y, x is a Vickers hardness of the magnetic core material, expressed in N / mm2, y is a fracture toughness of the magnetic core material, expressed in N / mm, and 2 ≤ Z ≤ 8.25. The magnetic core material of the present invention exhibits excellent crack resistance when used in coated inductors, improves reliability of coated inductors using said magnetic core material, and effectively reduces magnetic core material cracking risks during coated inductor use.

The application discloses a material crack data acquisition and graph construction method based on image processing and belongs to the technical field of material mechanical property analysis and image processing, and comprises the following steps: designing an arc-shaped polymethyl methacrylate sample; eliminating sample machining residual stress by using a constant-temperature and constant-humidity test box, combining a servo control tension testing machine to apply a constant load and recording crack generation time, simultaneously observing crack state and capturing crack morphology images by using a microscope and a camera; performing multi-step processing on the crack morphology images; performing crack equivalent node characterization and constructing a crack network based on a K nearest neighbor algorithm and modularity optimization; dividing community structures by using a community detection method based on modularity optimization to optimize modularity, and finally realizing efficient quantitative analysis of crack evolution rules. The application can accurately extract crack micro features and reveal crack propagation rules through networked characterization, and provides a standardized and quantifiable technical means for brittle material fracture mechanism research.

The utility model relates to the technical field of silencers, and discloses a silencer assembly which comprises a cylinder body, stamping end covers are fixed at two ends of the cylinder body, pressing grooves are arranged on outer side surfaces of the stamping end covers in an array mode, connecting sleeves are fixed on the stamping end covers, silencing hole pipes are fixed in the connecting sleeves, red copper transition terminals are fixed at one ends of the silencing hole pipes, and the red copper transition terminals are fixed at the other ends of the silencing hole pipes. Silencing holes are formed in the silencing hole pipe in an array mode, and the stamping end cover is connected with the cylinder body in a welded mode. After the silencer assembly and the cylinder body are integrally formed, the stamping end covers which are independently formed are arranged at the two ends of the cylinder body, cold hardening in the material spinning process is reduced, the material cracking defect is avoided, the silencer avoids repeated spinning and rolling, the production cost is reduced, the machining efficiency is improved, the combination modes of the two ends of the cylinder body are diversified, and the practicability is high. The silencer assembly is suitable for various silencer structures, the stamping end cover is independently connected with the silencing hole pipe and the barrel in a welded mode, operation is easy, the production difficulty is lowered, and the service life of the silencer assembly is prolonged.

The utility model relates to aluminium material processing technical field relates to a feeding gate structure. The inlet on the feed frame is arranged on the feed inlet on the furnace body, the sealing gate on the two movable racks is matched with the inlet, the drive mechanism drives two movable racks to move relatively along the feed frame in horizontal direction, and the hanging part drives the sealing gate to move up and down along the vertical direction of the movable rack, the sealing operation of the inlet is carried out under the dead weight of the sealing gate, it is simple to operate, effectively prevents the heat of aluminium material cracking to spread outward, improves the sealing heat insulation effect of feeding gate, effectively maintains that the temperature in aluminium material cracking furnace does not dissipate from the inlet, guarantees the temperature in the furnace, and simultaneously adopts the hanging part to separate the movable rack and the sealing gate, compared with the direct drive gate mode, effectively reduces the weight of the sealing gate, reduces the weight of the movable rack, then the weight of the sealing gate does not need to be limited, can effectively increase the size of the sealing gate.

The invention discloses a titanium / aluminum alloy fatigue life prediction method considering a material crack tip plastic zone, and belongs to the technical field of material and structure fatigue life evaluation. The method comprises the following steps: acquiring a material parameter and a load; the crack tip plastic zone energy dissipation model is corrected, and the fatigue crack initiation life is calculated; determining a calculation starting point based on an equivalent initial defect size method, and calculating the crack propagation life by using an NASGRO equation; and finally summing to obtain the total life. According to the method, the defects that a traditional empirical model is insufficient in physical property and an existing physical model ignores plastic dissipation and is difficult to link short crack propagation are overcome, and full-period and high-precision life prediction from microcosmic initiation to macroscopic fracture is achieved through physical criteria and an equivalent method.

The invention discloses a four-point bending stress corrosion test fixture for an irradiation sample in a high-temperature molten salt environment and a test method of the four-point bending stress corrosion test fixture. The fixture comprises a main stretching rod, a kettle cover, a position deviation adjuster, a counter-force frame, four secondary stretching rods, a counter-force plate, a loading block support, a sample table, a positioning pin, a loading block and a fixing pin, a reverse stretching mode is adopted, a main stretching rod is pulled upwards through a servo stretching machine, a secondary stretching rod, a sample table and a sample are sequentially driven to move upwards, the sample is subjected to counter-acting force of a loading block in the upward moving process, the lower surface is bent, and tensile stress is generated; therefore, the material cracking research of the sample under the joint coupling of irradiation, high-temperature molten salt corrosion and stress is realized. According to the method, the limitation of an existing research scheme is broken through, the relationship between the sample surface stress and the applied load is established by adopting a four-point bending method and combining finite element analysis, the stress of a sample irradiation surface is strictly controlled, the research of multi-environment coupling is realized, and the period of experimental research and the cost of a single experiment are reduced.