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35 results about "Uniaxial tension" patented technology

Uniaxial Tension (UT) Testing. The uniaxial tension test is one of the most commonly used tests to determine important material parameters such as Young’s modulus, yield strength, ultimate strength, elongation at break, Poisson’s ratio, and Lankford coefficients (r-values).

Damage-considered solder bump viscoplastic constitutive model establishing method

The invention relates to a method for establishing a viscoplastic constitutive model of a solder bump considering damage. Comprising the following steps: performing a uniaxial tension and compression test on a solder bump sample to obtain a macroscopic stress-strain curve of the sample; a unit cube finite element model is established, the unit cube finite element model adopts the solder constitutive model constructed in the step (2), loads are set for the model for numerical simulation, and a stress-strain curve calculated by the model is obtained; and fitting the stress-strain curve obtained by simulation in the step (3) with the macroscopic stress-strain curve obtained by the tension and compression test in the step (1) through a test parameter method, and determining parameters of the solder constitutive model, so that the final solder bump viscoplastic constitutive model considering the damage is established. The method can accurately predict the deformation and other mechanical behaviors of the solder under the thermal-force loading condition, and can be widely applied to fatigue life prediction and reliability evaluation of the electronic packaging structure.
Owner:NANJING UNIV OF SCI & TECH

Evaluation method for rapidly predicting formability of sheet metal

The invention provides an evaluation method for rapidly predicting the formability of a plate. The evaluation method comprises the following steps: S1, preparing a standard dumbbell-shaped uniaxial tensile sample; s2, preparing a plane strain tensile sample; s3, performing uniaxial tension on the standard dumbbell-shaped uniaxial tension sample; s4, performing uniaxial tension on the plane strain tensile sample; s5, calculating abscissa and ordinate values of three key feature points in the forming limit curve according to the material thickness t, the first correction coefficient and the second correction coefficient; s6, correcting the numerical value of the ordinate in the key feature point by using the first correction coefficient and the second correction coefficient to obtain a corrected ordinate; s7, drawing a forming limit judgment curve; and S8, the forming limit judgment curve is input into finite element simulation analysis software. The method greatly improves the analysis efficiency and prediction precision of the formability of the sheet metal, is especially suitable for the occasion of forming analysis of metal sheet parts, and widely meets the application requirements of engineering practice and scientific research work.
Owner:ANGANG STEEL CO LTD

Method and device for predicting crack path of 3D printing part based on generative adversarial network

The invention discloses a 3D printing part crack path prediction method and device based on a generative adversarial network. Acquiring a hole image through X-ray CT and binarizing the hole image; a high-fidelity phase field fracture mechanics (PFM) model is used for extracting an SED field in an elastic stage (epsilon = 0.1%) under uniaxial stretching, simulation is carried out till fracture is carried out, a real crack path is obtained, and the SED field and the real crack path serve as labels; a cascaded cGAN containing G1, G2, D1 and D2 is constructed, the G1 is used for predicting an SED field through the hole diagram, and the G2 is used for predicting a crack path through the SED field; d1 is used for distinguishing the authenticity of an SED field, and D2 is used for distinguishing the authenticity of a crack path; mAE and confrontation loss combined training is adopted; during prediction, a crack path can be output in a second level only by inputting a hole image. According to the method, the problem of rapid prediction of discontinuous cracks under complex random holes is solved, the accuracy rate reaches 90%, the efficiency is improved by more than 104 times compared with that of a traditional method, and the engineering value is remarkable.
Owner:WUHAN UNIV

Stress-strain relation estimation method

A stress-strain relationship estimation method according to the present invention comprises: a step (S1) for performing a torsion test on a first round bar test piece (10) to obtain a relationship between a torsion torque and a torsion angle; a step (S3) in which a torsion test is performed on a second round bar test piece (10) having a parallel section (11) having a smaller radius than the first round bar test piece (10), and the relationship between the torsion torque and the torsion angle is obtained; a step (S5) in which the relationship between the shear stress and the surface shear strain is obtained on the basis of the relationship between the torsion torque and the torsion angle obtained by the respective torsion tests of the first round bar test piece (10) and the second round bar test piece (10); and a step (S7) in which the shear stress and the surface shear strain are converted into uniaxial tensile stress and strain, and the relationship between the stress and the strain is estimated.
Owner:JFE STEEL CORP

A high-throughput modeling and computing method and system for metal matrix composites

The present application relates to the technical field of metal matrix composites, and provides a high-throughput modeling and calculation method for metal matrix composites, comprising the following steps: S1: determining the parameters of particles and matrix in different particle reinforced metal matrix composites; S2: establishing brick masonry configuration, multi-core structure and Belytschko configuration based on the parameters of particles and matrix; S3: establishing gradient distribution configuration based on the parameters of particles and matrix, including surface layer hard structure and core layer hard structure and cobweb structure; S4: establishing honeycomb structure, micro-tube structure and uniform structure based on the parameters of particles and matrix; S5: batch setting of boundary conditions required for each model in uniaxial tension, creating and gradually submitting jobs, and automatically extracting parameters including stress-strain curve, stress nephogram and energy release rate at any moment of uniaxial tension. The present application solves the problem of reducing the cost required for exploring high-performance materials in high-throughput modeling and calculation of particle reinforced metal matrix composites.
Owner:SHANGHAI JIAOTONG UNIV

Discrete ballastless track tension and compression fatigue damage rapid calculation method

The invention provides a discrete ballastless track tension-compression fatigue damage rapid calculation method, which comprises the following steps of: uniformly measuring a complex stress state and a simple stress state through a damage energy release rate, and decomposing tension-compression effective stress by utilizing a fourth-order projection tensor, so that the tension-compression effective stress value is equivalent to a uniaxial tension-compression stress value under a uniaxial loading condition; constructing a hyperbolic function with a natural constant as a base and a damage variable as an index on the basis of the damage energy release rate and in combination with three-stage damage characteristics of high-cycle fatigue of the material; carrying out integration on fatigue loading times through tension and compression damage, and deducing to obtain a discrete transcendental differential function of the damage related to the loading times; function variables are defined, an initial value is set, an iteration format is established, the discrete transcendental differential function is solved through a numerical integration method, and a calculation result graph is drawn. The model is simplified, and the calculation efficiency is improved; a high-order tensor stress updating algorithm does not need to be constructed, redundant calculation is reduced, and the data processing efficiency and the calculation speed during parameter analysis are greatly improved.
Owner:SOUTHWEST JIAOTONG UNIV

Three-dimensional numerical simulation method capable of predicting constitutive behavior of chopped aramid fiber reinforced rubber composite material

The invention discloses a three-dimensional numerical simulation method capable of predicting constitutive behaviors of a chopped aramid fiber reinforced rubber composite material. According to the simulation method, a finite element numerical model is adopted, the finite element numerical model is a three-dimensional cuboid model, a model main body is a rubber matrix, chopped aramid fibers are randomly distributed in the model, the chopped aramid fibers are cylindrical, and the contact relation between the rubber and the chopped aramid fibers is simulated by adopting a finite element embedding unit technology. Grids of the rubber and the chopped aramid fibers in the embedded unit model are mutually independent and are in regular shapes, uniaxial stretching of the chopped aramid reinforced rubber composite material is simulated by adopting a mixed boundary condition, and a stress-strain curve of the chopped aramid reinforced rubber composite material is obtained. Compared with a traditional three-dimensional finite element model, the model obtained through the simulation method is high in mesh quality, suitable for the situation that the ratio of the fiber modulus to the matrix modulus is large and the length-diameter ratio of fibers is large, and capable of truly simulating the constitutive mechanical behavior of a test piece.
Owner:QUANZHOU NORMAL UNIV +1

In-situ variable-temperature tensile device and testing method for grazing-incidence X-ray scattering characterization

This application relates to the field of thin film testing technology, and discloses an in-situ variable temperature tensile device and a testing method for grazing incidence X-ray scattering characterization. The device includes a power assembly, a base, a slide rail, a support assembly, and a heating assembly. The slide rail is arranged at the upper end of the base; the support assembly includes a first platform support and a second platform support. A first pressing piece is arranged at the upper end of the first platform support, and a second pressing piece and a tensile sensor are arranged at the upper end of the second platform support. Both the first platform support and the second platform support are movably arranged on the slide rail. The first pressing piece cooperates with the second pressing piece to fix the thin film sample. The first platform support and the second platform support are connected to the power assembly; the heating assembly is arranged on the base and is located between the first platform support and the second platform support. This application provides valuable information for the in-situ structural evolution of various functional thin films under tensile conditions, and can also characterize the temperature dependence of the molecular packing structure of functional thin films under uniaxial tension.
Owner:TIANJIN UNIV

A method for uniaxial tension testing using a biaxial tensile testing machine

This invention relates to a method for uniaxial tensile testing using a biaxial tensile testing machine, belonging to the fields of simulation and material forming technology. The method includes: adding a tensile mode to the biaxial testing machine control model, shielding the Y-axis tensile setting to achieve independent X-axis tensile testing; designing the tensile specimen as a dumbbell-shaped specimen with a length of 320 mm, a shoulder width of 63 mm on both sides, and a center width of 50 mm; applying five strain points to the dumbbell-shaped specimen—one in the center and four on the outer edges—arranged in a cross pattern; placing the dumbbell-shaped specimen on the biaxial testing machine to perform a tensile test and plotting the yield surface. This invention uses a biaxial tensile testing machine to achieve uniaxial tensile testing, enabling all basic measurements for yield surface calculation to be completed on a single device, eliminating systematic errors, and improving measurement efficiency and accuracy.
Owner:INNER MONGOLIA BAOTOU STEEL UNION

A three-dimensional fatigue crack growth behavior prediction method considering surface strengthening effect

The present invention discloses a three-dimensional fatigue crack growth behavior prediction method that considers the surface strengthening effect. The method comprises the following steps: performing surface strengthening on a metal material specimen, characterizing the residual stress of the strengthened metal material specimen, obtaining the gradient distribution of the residual stress inside the metal material specimen, and obtaining the three-dimensional spatial distribution function of the residual stress inside the specimen through numerical fitting. Based on the performance parameters of the metal material, model parameters for fatigue crack growth calculation are obtained through uniaxial tension calculation and fatigue strength calculation. According to the three-dimensional spatial distribution function of the residual stress, the performance parameters and model parameters of the metal material are combined with the residual stress, and a three-dimensional fatigue fracture phase field calculation model is used to predict the fatigue crack growth behavior of the metal material. Considering the influence of the surface strengthening treatment on the residual stress distribution inside the material, a three-dimensional fatigue fracture phase field model considering the gradient structure is established, which is beneficial for improving the prediction of the effect of surface treatment on the fatigue performance of the material.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Clamping device for out-of-plane uniaxial tension and fatigue test of fiber reinforced composite material

The invention discloses a fiber reinforced composite material out-of-plane uniaxial tension and fatigue test clamping device, and belongs to the technical field of material mechanical property testing equipment.The device comprises a fixing assembly connected with a testing machine and a self-centering assembly connected with a test piece, and the fixing assembly is movably connected with the self-centering assembly; the self-centering device is used for self-centering of direct loading of the test piece. By adopting the clamping device for the out-of-plane uniaxial tension and fatigue test of the fiber reinforced composite material, self-centering of direct loading of a test piece is realized, the accuracy and reliability of a test result are improved, and the test cost is reduced.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Mechanical property evaluation method based on cover layer tension failure and shear failure

The invention relates to the technical field of oil-gas exploration, in particular to a mechanical property evaluation method based on cover layer tensile failure and shear failure. The method comprises the steps that firstly, cover layer tensile strength parameters and cover layer shear strength parameters are synchronously obtained through uniaxial tension and triaxial compression tests; secondly, calculating a tensile failure critical pressure and a shear safety index respectively by combining ground stress test data; by introducing a weight coefficient, a mechanical property index S evaluation model fusing tension and shear failure is constructed to divide risk grades; finally, the safe operation pressure range of the gas storage is optimized according to the function relation between the mechanical property index of the cap layer and the operation pressure of the gas storage, the limitation that only a single failure mode is considered traditionally is broken through, comprehensive evaluation on the stability of the cap layer is achieved by quantifying the coupling effect of tension-shear failure, and the reliability of the cap layer is improved. The method is especially suitable for safety evaluation of the gas storage cover layer under complex geological conditions, and provides more accurate risk early warning and pressure regulation and control basis for engineering practice.
Owner:CHONGQING NATURAL GAS STORAGE & TRANSPORTATION CO LTD

In-situ measurement device for hydrogen permeability of composite material under uniaxial tension

The invention provides an in-situ measurement device for hydrogen permeability of a composite material under uniaxial tension. The in-situ measurement device comprises a test stand; the fixed tensile fixture is mounted on the test stand, the fixed tensile fixture comprises a first clamping assembly and a second clamping assembly, and the first clamping assembly and the second clamping assembly are used for clamping the two ends of the to-be-tested sample in the axial direction respectively; the measuring module is mounted on the test stand, the measuring module comprises a first contact assembly and a second contact assembly, the first contact assembly and the second contact assembly are used for being in contact with the two side surfaces of the to-be-tested sample in the horizontal direction respectively, each of the first contact assembly and the second contact assembly comprises a permeation chamber facing the to-be-tested sample, and the permeation chambers are suitable for being filled with hydrogen; the measurement module is configured in a way that after the to-be-tested sample is stretched at a preset temperature, the first contact assembly and the second contact assembly respectively clamp the to-be-tested sample from two sides for sealing, so that a penetration test is carried out. According to the invention, on the basis of in-situ measurement, the accuracy of hydrogen permeability testing can be improved.
Owner:TECHNICAL INST OF PHYSICS & CHEMISTRY - CHINESE ACAD OF SCI

Shiftless anchor chain out-of-plane bending fatigue experiment loading device and loading method thereof

The invention discloses a gear-free anchor chain out-of-plane bending fatigue test loading device and a loading method thereof, the gear-free anchor chain out-of-plane bending fatigue test loading device comprises a group of loading devices, a series of gear-free anchor chains with different sizes and a series of testing devices, and the out-of-plane bending fatigue test of the gear-free anchor chains is completed through axial cyclic loading and radial cyclic loading of loading equipment. The test anchor chain is installed on the loading equipment, the out-of-plane bending fatigue test process of the test anchor chain is completed through axial cyclic loading and radial cyclic loading of the loading equipment, anchor chains of different sizes are tested through the loading equipment, and it is guaranteed that the anchor chain enters an unstable fracture state. The complete out-of-plane bending fatigue state of the anchor chain is obtained by measuring the strain, the inclination angle, the cycle index and the applied force of different anchor chains at the fatigue fracture moment in the out-of-plane bending loading state. The device supplements the uniaxial tension constant load to obtain the gap of the fatigue state of the anchor chain, and has the advantages of convenient operation, safe test, high efficiency, low cost and the like.
Owner:JIANGSU UNIV OF SCI & TECH

Elasto-plastic constitutive parameter calculation method

The application discloses an elasto-plastic constitutive parameter calculation method, comprising the following steps: S1, performing uniaxial tension experiment, obtaining a true stress-true strain curve of the experiment, and performing intercept processing near the maximum stress to obtain an intercepted curve; S2, based on the intercepted curve, extracting data points according to an equal arc length method, and performing data compression; S3, through a selected elastic model and a plastic model, performing nonlinear analysis on each data point, obtaining the proportion of elasticity and plasticity in the strain increment at each data point, and calculating the true stress-true strain curve of the model. According to the application, data points are extracted according to the arc length, the operation speed is improved under the condition that appropriate data points are selected, the elasto-plasticity of the data points is decomposed, the rationality of the mechanical calculation is ensured, the global optimization of the elasto-viscoplastic constitutive parameter is performed by constructing an optimization objective function, the coordination of the elastic and plastic constitutive parameters is ensured, and the calculation precision is improved.
Owner:CHONGQING INNOVATION CENTER OF BEIJING INSTITUTE OF TECHNOLOGY

Lattice material that simultaneously expands or contracts under tension and compression

The application provides a lattice material which expands or shrinks simultaneously under tension and compression, first, the structural response form is converted with the direction of external force by designing the contact mode in the structure, then the stiffness difference between the S-shaped rib plate and the straight rib plate forms two types of lattice materials which can expand or shrink in the transverse direction under uniaxial tension or compression in a specific direction, and the two types of lattice materials can also shrink or expand simultaneously in the orthogonal direction, showing the characteristics of opposite deformation. The structure and material of the application can be used as a specific functional material, and have application prospects in the fields of sensing, energy absorption and shock absorption, wave propagation and mechanical logic control.
Owner:BEIJING UNIV OF TECH

Micro-magnetic detection method for predicting uniaxial tensile stress-strain based on convolutional neural network

The application discloses a micro-magnetic detection method for predicting uniaxial tensile stress and strain based on a convolutional neural network, and relates to the technical field of micro-magnetic detection, which comprises the following steps: vertically attaching a micro-magnetic sensor to the surface of a standard tensile test piece; in the process of a tensile experiment, acquiring micro-magnetic signals of the standard tensile test piece in different states, and simultaneously measuring stress and strain data at corresponding times; processing the micro-magnetic signals to obtain various micro-magnetic characteristic parameters; merging the micro-magnetic parameters and the stress and strain states by aligning the standard tensile experiment of classical mechanics and the time of the micro-magnetic signals to form a multi-micro-magnetic signal data set; based on the multi-micro-magnetic signal data set, adopting a strategy of reducing a learning rate and multiple loss to train a one-dimensional convolutional neural network, and then predicting the corresponding stress and strain of the structure. Therefore, the micro-magnetic detection method for predicting uniaxial tensile stress and strain based on the convolutional neural network can be used to predict the stress and strain curve of a steel structure component subjected to uniaxial tension and containing an elastic segment and a plastic segment.
Owner:GUANGZHOU UNIVERSITY

An intelligent perception-based asphalt pavement semi-rigid base crack monitoring method

The application discloses an intelligent sensing-based asphalt pavement semi-rigid base crack monitoring method, which is characterized in that: an electric resistance sensor integrated intelligent particle is buried in the asphalt pavement semi-rigid base to collect the mechanical response of the pavement structure, and the base crack is monitored. The steps are as follows: based on the conversion relationship of the macroscopic and microscopic parameters calibrated by the uniaxial tension and compression simulation experiment, a cross-scale pavement model is established by adopting a finite element-discrete element coupling method; through numerical simulation of the base crack evolution, the base crack is tracked and positioned by combining the Westergard complex variable function method of the I-II type composite crack of fracture mechanics; the intelligent particle is buried in the base of the pavement model to collect information, and according to the stress concentration characteristics of the crack neighborhood, the matching of the intelligent particle monitoring index and the extraction of the sensitive range are realized; the intelligent particle laying scheme for the semi-rigid base crack monitoring and positioning is established, and the monitoring of the semi-rigid base crack position and the expansion stage is realized.
Owner:SOUTHEAST UNIV

Method for calculating fatigue behavior of gradient structure metal based on deformation mechanism and microstructure composition

The invention discloses a method for calculating the fatigue behavior of gradient structure metal based on a deformation mechanism and microstructure composition. According to the method, based on a deformation mechanism and microstructure composition, a gradient grain size distribution nanostructure metal low-cycle fatigue hysteresis curve can be simulated, and the fatigue life can be predicted. Under an elastic-plastic theoretical framework, microstructure characteristics such as grain size, dislocation density and microcracks in metal are comprehensively considered, and elastic-plastic constitutive and toughness characteristics during uniaxial tension / compression are accurately simulated through numerical calculation. When a low-cycle fatigue hysteretic curve is simulated, cyclic strain loading conditions are set on the basis of the elastic-plastic constitutive model, a curve is generated through numerical calculation, the curve shape, area change and cyclic hardening / softening behaviors can be accurately captured, and a fatigue life prediction model is established according to the curve shape, area change and cyclic hardening / softening behaviors. The model can accurately predict the fatigue life according to a microstructure and loading conditions by combining microscopic and macroscopic relations. The method provides a new way for low-cycle fatigue simulation and life prediction, and provides theoretical guidance for prolonging the life of the gradient material.
Owner:ZHEJIANG UNIV

A finite element simulation method for compartment joints in foundation slabs using the skip-compartment method

The present invention discloses a finite element simulation method for compartment joints in foundation slabs using a skip-bin method. The method comprises the following steps: a commonly used compartment joint structure in a foundation slab includes a compartment block A, a compartment block B, a contact surface, a waterstop steel plate, and bottom slab reinforcement; solid elements are used to simulate the compartment blocks, viscous elements are used to simulate the contact surface, bushing elements are used to simulate the waterstop steel plate, and truss elements are used to simulate the reinforcement; the bond-slip characteristics of the compartment joints are simulated using viscous elements, and the parameters of the traction-separation constitutive model are determined by inverse analysis using a PSO-SVM algorithm based on uniaxial tension test results. The finite element simulation method for compartment joints in foundation slabs using the skip-bin method can simultaneously consider detailed components such as the contact surface, the waterstop steel plate, and the bottom slab reinforcement. Furthermore, the mechanical properties of the compartment joints can be refined by simulating the bond-slip characteristics of the contact surface and the waterstop steel plate, and the mechanical parameters of the viscous elements can be quickly and accurately determined. This improves the accuracy of the finite element simulation of foundation slabs using the skip-bin method.
Owner:CHINA MCC5 GROUP CORP LTD

Optimization method of GTN micro-damage model parameters based on GA-BP neural network algorithm

The present invention belongs to the field of material analysis technology and discloses a method for optimizing parameters of a GTN mesoscopic damage model based on a GA-BP neural network algorithm. The method comprises the following steps: Step 10, experimentally obtaining a measured stress-strain curve of a material to be tested; Step 20, numerically simulating uniaxial tension of the GTN mesoscopic damage model using finite element analysis to obtain a simulated stress-strain curve, and correcting the damage parameters using a finite element inverse calibration method; Step 30, varying the maximum stress and maximum strain, and repeating uniaxial tension tests using finite element analysis to obtain multiple sets of sample data; Step 40, inputting a training set of data into the GA-BP neural network model to obtain an optimized BP neural network model; and Step 50, inputting a test set of data into the optimized BP neural network model, determining the optimal test set of data, and using the corresponding output as the final GTN mesoscopic damage model parameters. The present invention reduces simulation and correction time and improves the accuracy and universality of damage parameter determination.
Owner:TAIYUAN UNIVERSITY OF TECHNOLOGY

Method and device for checking single-axis tensile-shear strength of diamond-shaped grid structure

The invention belongs to the technical field of aircraft design, and relates to a method and a device for checking single-axis tensile-shear strength of a rhombic grid structure. The method comprises the steps that S1, the side length L, the long diagonal size 2a, the short diagonal size 2b and the beam frame width h of a grating unit are determined, the grating unit is a minimum repeated unit forming a grating structure, the grating unit is a rhombic beam frame, and the grating structure is a part of a full-aircraft structure; s2, axial tensile loads applied to the two ends of the long diagonals of the grating units and axially symmetrical shear loads applied to the four ends of the grating units are obtained; and S3, the safety margin of the grid units is determined. According to the method, the calculation time is shortened, and the structure parameter iteration speed is increased.
Owner:XIAN AIRCRAFT DESIGN INST OF AVIATION IND OF CHINA

An electromagnetically driven Hopkinson bar multiaxial tension-compression composite system

The invention discloses an electromagnetically driven Hopkinson bar multi-axial tension-compression composite system, which relates to the technical field of dynamic mechanical property testing of materials. The system comprises N optical splitters, M photoelectric signal processors, and M electromagnetically driven Hopkinson bar uniaxial tension-compression systems. In the uniaxial tension-compression system, a tensile baffle is provided at the head end of an incident bar, a compression baffle is provided at the middle part, and the tail end is connected to a sample to be tested. An impact armature is sleeved on the incident bar. A coil accelerator is sleeved on the impact armature and connected to the photoelectric signal processor. Each optical splitter divides an initial control signal output by a host computer into M synchronous control signals and sends them to each photoelectric signal processor. Each photoelectric signal processor generates a working signal according to a control instruction and the N synchronous control signals. Each coil accelerator drives the impact armature to impact the tensile baffle or the compression baffle according to the working signal. The invention realizes tensile drive, compression drive, and a control combination test of tensile and compression drive on the sample to be tested.
Owner:INST OF ELECTRICAL ENG CHINESE ACAD OF SCI

Method for predicting tensile yield strength of different orientations of magnesium alloy extruded bar

The application discloses a method for predicting tensile yield strength of magnesium alloy extruded rods in different orientations, and mainly comprises the following steps: establishing a yield strength distribution equation model, testing yield strength in any two orientations, calculating the yield strength distribution equation in a yield space, further calculating the change of the yield strength along the loading direction, and predicting the yield strength. The yield strength distribution equation can be obtained through twice uniaxial tensile tests, and the yield strength of the magnesium alloy extruded rod in different orientations during uniaxial tension can be obtained through further calculation, so that the yield strength of the magnesium alloy extruded rod with strong basal plane texture can be accurately predicted.
Owner:JIANGSU UNIV OF SCI & TECH

Collet-chuck system for uniaxial testing

The disclosure relates to apparatus and methods for uniaxial testing of a solid specimen, such as an asphalt or asphalt concrete specimen. The apparatus provides a simplified and accelerated procedure for mounting and testing asphalt mixture samples and other solid specimens under uniaxial tension and / or compression, in particular to measure corresponding uniaxial strain and / or fatigue in the specimen. The apparatus incorporates two opposing collet-chuck elements to rapidly mount and fixedly hold a solid specimen in place in a loading system to apply uniaxial loads. The disclosure further relates to an off-specimen means for measuring strain in a specimen using optical imaging in which successive time series images of a specimen during uniaxial loading can be analyzed to determine displacements and corresponding strains.
Owner:ENG & SOFTWARE CONSULTANTS LLC +1

Method for evaluating crack resistance of asphalt cement based on asphalt-aggregate constraint simulation

The invention relates to the technical field of road engineering asphalt pavement material performance detection, in particular to an asphalt cement anti-cracking performance evaluation method based on asphalt-aggregate constraint simulation, which comprises the following steps: preparing a cylindrical asphalt test piece completely bonded with circular bonding surfaces of a top die and a bottom die; placing the test piece at a preset temperature, and keeping the temperature constant until the temperature is uniform and stable; mounting the test piece subjected to heat preservation on a tensile testing machine, performing uniaxial stretching on the test piece in a preset loading mode in a constant-temperature environment consistent with S2 until the test piece is completely snapped, and continuously collecting real-time load and displacement in the whole stretching process; calculating an anti-cracking index based on the collected load and displacement, and evaluating the anti-cracking performance of the asphalt cement; a rigid constraint interface is constructed through a standardized test piece preparation process, a multi-dimensional constraint stress state and a real cracking mechanism of asphalt among aggregates are reproduced in a uniaxial stretching process, and a whole-process standardized system from test piece preparation, constant-temperature loading to data evaluation is constructed.
Owner:JSTI GRP INSPECTION & CERTIFICATION CO LTD +1

Simulation method of uniaxial tensile behavior in liquid lead-bismuth environment

This invention relates to a method for simulating the uniaxial tensile behavior of a liquid lead-bismuth environment. The method involves conducting uniaxial tensile tests on metallic material specimens in an air environment to obtain stress-strain curves; establishing a two-scale finite element model of the metallic material specimen using ABAQUS finite element software and simulating the uniaxial tension of the two-scale finite element model in the air environment; conducting fracture toughness tests and uniaxial tensile tests on the metallic material in a liquid lead-bismuth environment to obtain stress-strain curves; and simulating the uniaxial tension of the two-scale finite element model in the liquid lead-bismuth environment using ABAQUS finite element software. This invention establishes a finite element model and uses ABAQUS finite element software for calculation, allowing for intuitive observation of the damage behavior of metallic materials during tensile processes in both air and liquid lead-bismuth environments. The established model and parameters can predict different structures and boundary conditions, offering advantages such as accurate results, high efficiency, and low cost. The established two-scale finite element model effectively reduces computational costs.
Owner:TIANJIN UNIV

High-throughput modeling and calculating method and system for metal-based composite material

The invention relates to the technical field of metal-based composite materials, and provides a metal-based composite material high-throughput modeling and calculating method which comprises the following steps: S1, determining parameters of particles and a matrix in different particle reinforced metal-based composite materials; s2, building a brick building structure, a multi-core structure and a Beliogang structure based on the parameters of the particles and the matrix; s3, establishing a gradient distribution configuration based on the particle and matrix parameters, wherein the gradient distribution configuration comprises a surface layer hard structure, a core layer hard structure and a cobweb structure; s4, establishing a honeycomb structure, a micro-tube structure and a uniform structure based on the parameters of the particles and the matrix; and S5, setting boundary conditions required to be set by each model during uniaxial stretching in batches, creating and gradually submitting operation, and automatically extracting parameters including a stress-strain curve, a stress nephogram and an energy release rate at any moment of uniaxial stretching. The problem of reducing the cost required for exploring a high-performance material in high-throughput modeling and calculation of the particle reinforced metal matrix composite material is solved.
Owner:SHANGHAI JIAOTONG UNIV

Method for calculating high-temperature elastic-plastic constitutive behavior and toughness characteristic of crystal-amorphous biphase metal based on deformation mechanism and microstructure composition

The invention discloses a method for calculating high-temperature elastic-plastic constitutive behaviors and toughness characteristics of crystal-amorphous double-phase metal based on a deformation mechanism and microstructure composition, which is based on an elastic-plastic theoretical framework, considers the deformation mechanism and the microstructure composition, realizes numerical calculation through MATLAB (matrix laboratory), and calculates the high-temperature elastic-plastic constitutive behaviors and toughness characteristics of the crystal-amorphous double-phase metal based on the deformation mechanism and the microstructure composition. And the high-temperature uniaxial stretching / compression elastic-plastic constitutive behavior and the toughness characteristic of the crystal-amorphous biphase metal are simulated and predicted. According to the method, microstructure characteristics such as metal internal grain size, dislocation density evolution, microcrack generation and evolution and amorphous integral number evolution along with temperature are considered, and high-temperature uniaxial tension / compression elastic-plastic constitutive behaviors and toughness characteristics of metal materials with microstructures composed of crystal phases and amorphous phases are simulated and predicted. In the preparation of a crystal-amorphous biphase metal material and a high-temperature mechanical property measurement experiment, a theoretical basis is provided for the high-temperature tensile / compressive property change of the crystal-amorphous biphase metal, and a theoretical guidance can be provided for improving the high-temperature mechanical property of the crystal-amorphous biphase metal.
Owner:ZHEJIANG UNIV

A multi-axial variable amplitude fatigue life prediction method based on critical plane

The present application relates to the technical field of multi-axis mechanical fatigue, and particularly relates to a multi-axis variable amplitude fatigue life prediction method based on a critical plane. The uniaxial tension-compression fatigue limit and pure torsional fatigue limit of a metal material, the tensile yield strength and shear strength are obtained; the fatigue performance parameters, static force performance parameters and multi-axis fatigue loading soft coefficients of each level of load of the metal material are calculated to determine the critical plane of the metal material; the equivalent fatigue damage parameters on the critical plane of each level of load are obtained, and the fatigue life of the metal material under multi-axis variable amplitude loading conditions is obtained according to the equivalent fatigue damage parameters on the critical plane of each level of load. The present application is simple in form, and only needs to obtain the performance parameters of the metal material by consulting a manual to accurately predict the fatigue life of the metal material under multi-axis variable amplitude loading.
Owner:HEBEI UNIV OF TECH