New method for studying high-temperature dynamic tensile properties of metal materials


【Author】 Chen Xiaoan; Song Shuncheng;

【Author】 CHEN Xiao’an1,SONG Shuncheng1,2(1.Southwest Jiaotong University,School of Mechanics and Engineering,Chengdu 610031,China;2.National Key Laboratory of Science and Technology on Materials in Impact Environment,Ningbo 315103,China)

[Institution] School of Mechanics and Engineering, Southwest Jiaotong University; National Key Laboratory of Impact Environmental Materials Technology;

【Abstract】 The dynamic tensile properties of metal materials under high temperature conditions were tested using a self-designed improved separate Hopkinson tie rod device with a small heating device, and the modified Johnson-Cook model was used as the constitutive relationship of the material, and a proposed A damage model that fits the strain rate and temperature-related damage of metal materials in the elastic and plastic stages, and fits the parameters. The results show that the improved device can accurately control the heating rate and temperature and reduce the impact of rod end softening. Test results The relative error is less than 1.5%; the yield stress and fracture strain of the metal material 304 stainless steel have obvious temperature softening effects of positive strain rate effects, but the elastic modulus of the material has negative strain rate effects and negative temperature effects; calculated between 293-625K The results are in good agreement with the test results, indicating that this method can be used to test and estimate the high-temperature dynamic mechanical properties of materials and be used for engineering analysis. More reduction

【Key words】 Metal materials; Dynamic tensile properties; High temperature; Strain rate;