Method for determining constitutive model parameters of material at ultrahigh strain rate
A constitutive model and strain rate technology, applied in the analysis of materials, measuring devices, and the use of ultrasonic/sonic/infrasonic waves, can solve residual stress prediction errors, difficulty in obtaining material constitutive model parameters, and inability to accurately characterize the stress-strain relationship of materials and other issues to achieve a good general effect
Inactive Publication Date: 2013-10-23
XI AN JIAOTONG UNIV
View PDF4 Cites 12 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Due to the characteristics of the ultra-high strain rate in the laser shock strengthening process, the existing test methods cannot directly obtain the unidirectional stress-strain relationship of the material at the ultra-high strain rate, and it is difficult to obtain the constitutive model parameters of the material at the ultra-high strain rate, and thus cannot be accurately characterized. The stress-strain relationship of materials at ultra-high strain rates causes errors in the prediction of residual stress under the parameters of the existing rate-dependent constitutive model, and cannot accurately predict the distribution of residual stress fields after laser shock peening. Therefore, a measurement method suitable for ultra-high Method for Constitutive Model Parameters under Strain Rate
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0023] The present invention will be further described in detail below in conjunction with specific drawings and embodiments, which are explanations rather than limitations of the present invention.
[0024] see image 3 , the method for the present invention to measure the constitutive model parameters under the ultra-high strain rate of material, comprises the following steps:
[0025] 1) According to the basic mechanical property parameters of the material to be tested and the existing constitutive model parameters, assign the initial value A to the material to be tested 0 , carry out tensile test on the material to be tested, and obtain the material at quasi-static low strain rate (10 -4 ~10 -1 the s -1 ) under the stress-strain curve; the Hopkinson compression bar test is carried out on the material to be tested, and the material is obtained at a high strain rate (10 2 ~10 4 the s -1 ) under the stress-strain curve;
[0026] 2) Set the stress-strain curve obtained ...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention discloses a method for determining constitutive model parameters of a material at an ultrahigh strain rate, and belongs to the technical field of material characterization, test and numerical analysis. The method comprises the following steps of: acquiring stress strain curves of the material at a low strain rate and a high strain rate through a tension test and a Hopkinson pressure bar test, and reversely optimizing the constitutive model parameters by taking the stress strain curves at different strain rates as a target so as to obtain the optimized constitutive model parameters; performing laser shock peening on the surface of the material, performing surface profile and residual stress test on the material, performing laser shock peening numerical simulation under the boundary condition of actual laser shock parameters, performing spatial statistics on a numerical simulation residual stress value according to a spatial range determined by an X-ray diffraction stress, and reversely optimizing the constitutive model parameters again by taking the deformation quantity and a residual stress test value of an actual surface strengthening region as a target to so as obtain the final constitutive model parameters. The method is high in universality and applicable to a general metal material.
Description
technical field [0001] The invention belongs to the technical field of material characterization, testing and numerical analysis, and in particular relates to a method for measuring constitutive model parameters of materials at ultrahigh strain rates. Background technique [0002] Material tensile test refers to the test of determining the material properties under the axial tensile load, from which the stress-strain curve under the condition of lower strain rate is obtained. The Hopkinson compression bar test is a method based on one-dimensional stress wave theory and using high-speed impact to obtain the dynamic mechanical response curve of materials at high strain rates. The surface profiler measures the slippage between the stylus of the instrument and the surface of the material, so as to obtain the surface morphology of the material. X-ray stress measurement refers to the X-ray diffractometer emitting a monochromatic X-ray beam of a certain wavelength to the surface o...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More IPC IPC(8): G01N3/00G01B17/04
Inventor 臧顺来聂祥樊李少鹏赵洁刘俊华
Owner XI AN JIAOTONG UNIV