10 results about "Engineering stress" patented technology

The invention provides a macroscopic finite element simulation analysis method and device for a sealing element considering plastic deformation, and belongs to the field of sealing element design. The method comprises the following steps: acquiring an engineering stress-strain curve of a plastic material in a compression state; converting the engineering stress-strain curve into a real stress-strain curve; determining a yield limit, and taking a strain point corresponding to the yield limit as a demarcation point of elasticity and plastic deformation; an elastic section of a real stress-strain curve is extracted, the elastic modulus is calculated, and the Poisson's ratio is obtained through axial and transverse strain measurement in a uniaxial compression test; a true stress-strain curve plastic section is extracted, and a multi-linear isotropic hardening model is established; constructing a complete elastic-plastic constitutive model covering the elastic deformation area and the plastic deformation area; the stress distribution, the strain response and the contact performance of the plastic sealing element in a compression deformation state are simulated. According to the method and the device provided by the invention, the problem that the result does not conform to the reality due to the fact that only elastic modulus and Poisson's ratio are used in existing sealing element simulation can be solved.

This invention provides a method, apparatus, computer equipment, and medium for predicting the failure of a wheel disc, relating to the field of digital twin technology. The method includes the following steps: conducting a uniaxial quasi-static tensile test on a tensile test specimen to obtain the engineering stress-strain curve of the wheel disc; converting the engineering stress-strain curve into a true stress-strain curve; constructing a wheel disc failure prediction model under deterministic conditions based on the true stress-strain curve; performing sensitivity analysis on the quantified parameters of uncertainty; obtaining sample data under different working conditions through finite element calculation based on key parameters; constructing a maximum strain proxy model for the wheel disc based on the sample data; inputting the key parameters into the maximum strain proxy model to obtain the confidence interval of the wheel disc's rotational speed at the time of failure. This scheme, by constructing a maximum strain proxy model for the wheel disc, achieves high-precision full-domain simulation of the wheel disc's failure process, solving the problems of limited test measurement points and insufficient simulation accuracy.

The invention discloses a material parameter calibration method based on a porosity coupling damage model, and relates to the technical field of vehicles. The method comprises the following steps: acquiring an actual engineering stress-engineering strain curve of a to-be-calibrated material; a finite element model of the to-be-calibrated material is established based on the damage constitutive model, and the damage constitutive model comprises porosity parameters; performing simulation stretching on the finite element model of the to-be-calibrated material to obtain a simulation engineering stress-engineering strain curve of the to-be-calibrated material; adjusting the porosity parameter to enable the overlap ratio of the simulation engineering stress-engineering strain curve and the actual engineering stress-engineering strain curve to reach a preset threshold value, so as to determine the target porosity parameter of the to-be-calibrated material. Therefore, the product development period is effectively shortened, and the test cost is reduced.

The present application relates to the technical field of materials, and relates to a method for automatically solving the elastic modulus of a metal material under dynamic tension. Engineering stress-engineering strain data of a target metal material under dynamic tension are obtained and preprocessed. Based on the mechanical properties of the material, an engineering strain analysis range is determined. According to the engineering strain analysis range, elastic modulus analysis data are determined from the engineering stress-engineering strain data. Based on the elastic modulus analysis data, linear fitting is performed to determine a first fitting curve. Based on the elastic modulus analysis data and the first fitting curve, the engineering strain analysis range of the target metal material is redetermined. Based on the redetermined engineering strain analysis range, linear fitting is performed to determine a second fitting curve. The slope error between the first fitting curve and the second fitting curve is determined, and in the case where the slope error meets a preset error value, the slope of the second fitting curve is taken as the elastic modulus of the target metal material.

The invention belongs to the technical field of welding joint material characterization, and particularly relates to a method, system, equipment and medium for obtaining a welding joint high-precision model, and the method comprises the following specific steps: preparing a sample, carrying out a tensile experiment on the sample, determining a corresponding engineering stress-strain curve, establishing a finite element model, and outputting the engineering stress-strain curve of simulation inversion. And performing comparison iteration, calibrating and optimizing material parameters, and finally obtaining a high-fidelity welding joint material model. According to the method, the anisotropy property of the material performance of the whole area of the welding joint is fully considered, and three typical types of a base metal area, a heat affected area and a welding seam area are covered. A miniature sample local performance testing method is introduced, and accurate description of the mechanical property of the whole-area material of the welded joint is achieved. The method is suitable for different welding processes and various joint structure forms, has high universality, and can remarkably improve the safety evaluation simulation precision of the welding structure in a real service state.

The present application provides a macroscopic finite element simulation analysis method and device for seals considering plastic deformation, which belongs to the field of seal design. The method includes: obtaining the engineering stress-strain curve of the plastic material under compression; converting the engineering stress-strain curve into a true stress-strain curve; determining the yield limit, and using the strain point corresponding to the yield limit as the dividing point between elastic and plastic deformation; extracting the elastic section of the true stress-strain curve, calculating the elastic modulus, and obtaining the Poisson's ratio by measuring the axial and lateral strains in the uniaxial compression test; extracting the plastic section of the true stress-strain curve, and establishing a multilinear isotropic hardening model; constructing a complete elastic-plastic constitutive model covering the elastic deformation zone and the plastic deformation zone; simulating the stress distribution, strain response and contact performance of plastic seals under compression deformation. The method and device provided in the present application can solve the problem that the existing seal simulation only uses the elastic modulus and Poisson's ratio, resulting in results that are inconsistent with reality.

The invention discloses a steel structure residual mechanical property evaluation method based on steel strain aging, and relates to the technical field of material mechanics. According to the method, the mechanical property change shown after the steel is subjected to plastic damage, namely the steel strain aging effect, is taken as a core, and a steel engineering stress-engineering strain curve under different strain aging conditions is tested by adopting a two-stage test method; and establishing an evolution equation of the steel strain aging mechanical property index along with the plastic damage degree and a constitutive model of the steel strain aging mechanical property index. Based on a strain aging mechanical property constitutive model, a two-stage numerical simulation method is adopted to carry out refined numerical analysis on the residual mechanical properties of the steel structure with plastic damage. The technical bottleneck of plastic damage and strain aging effect coupling treatment in traditional finite element analysis is broken through, and a reliable quantitative evaluation method is provided for residual mechanical property evaluation of the steel subjected to plastic damage. The method for evaluating the residual mechanical properties of the steel structure has a wide application prospect.

The application provides a sleeve size parameter determination method based on surrounding rock borehole radial stiffness damage evaluation, and relates to the field of mechanics and test technology.The method comprises the following steps: according to the mining stress condition of the engineering site roadway surrounding rock, the basic mechanics parameters of the surrounding rock and the actual situation of the anchor rod support, the sleeve material selection and length parameters of the anchoring base body are determined in combination with the indoor test; the thickness parameters of the sleeve are determined on the basis of the engineering site, the anchoring borehole damage is judged, the stiffness damage of the anchoring hole is closely related to the plastic deformation and the rock modulus damage law, therefore, the plastic zone radius of the anchoring borehole is analyzed in combination with the engineering stress and the lithology condition, the modulus damage degree of the surrounding rock around the borehole is evaluated on the basis of the rock elastic modulus damage evolution law test and the theoretical analysis, and then the radial stiffness damage coefficient of the anchoring borehole is given, and finally, the thickness parameters of the anchoring base body sleeve are determined according to the equivalent mechanics of the engineering surrounding rock borehole and the sleeve radial stiffness, so that the scientificity of the sleeve parameter determination is ensured.

The application discloses a metal material cumulative damage model and a calibration method thereof, and the calibration method comprises the following steps: (1) carrying out uniaxial cyclic loading test to obtain an engineering stress-strain curve of the material; (2) calculating the Young's modulus E under different engineering strains; (3) calculating the cumulative damage D under different strains and obtaining data points of the cumulative damage and the engineering strain; (4) converting the data points of the cumulative damage and the engineering strain into data points of the cumulative damage and the equivalent plastic strain; and (5) calibrating the cumulative damage model parameters. Through the construction of the cumulative damage model and the design of the cyclic control conditions of the model parameter calibration test, the application realizes simple, fast and low-cost metal material cumulative damage test and fitting, obtains the equivalent plastic strain-cumulative damage curve which is closer to the actual situation of the metal material, and overcomes the problem that the existing model cannot accurately describe the cumulative damage behavior of the material.

The invention discloses a metal material plasticity large deformation constitutive parameter obtaining method and a product, the method comprises the following steps: carrying out a tensile test of a standard test piece to obtain an engineering stress-strain curve, converting a uniform deformation part into a real stress-strain curve by adopting a theoretical formula, and converting a softening section into a real stress-strain curve by adopting a theoretical formula; the method comprises the following steps: establishing a finite element model of a standard test piece, carrying out tensile simulation iteration, adjusting a stress-strain curve used in numerical simulation by comparing the difference between the stress-strain curves obtained by numerical simulation and test, and carrying out loop iteration to enable the stress-strain curves to be consistent with the actual stress-strain curve of the material. The plastic large deformation performance characterization of the material is realized; the method is convenient to implement, the obtained parameters can completely and reliably reflect the material mechanical characteristics of the material in the elastic section and the plastic section, and when the method is applied to structural response analysis, large deformation and even damage of the material can be more accurately reflected.