通过压入测试以获取工程服役结构、小型构件和焊接结构焊缝过渡区的材料单轴本构关系参数,且根据材料本构关系参数来估算材料的压入硬度对于工程设计和安全评估有重要意义。对于幂律材料,本文依据锥形压入试验原理和弹塑性接触有限元分析(EPFEA),揭示了不同锥角的锥形压头其压入能量比与屈服应力之间存在线性关系,提出了基于能量原理预测金属材料本构关系部分关键参数(弹性模量、屈服应力和硬化指数)的CR-EMI(Constitutive Rela-tionship based on Energy Method of Indentation)方法。同时,基于此种线性关系提出了由Hollomon本构关系模型参数预测硬度的H-EMI(Hardness based on Energy Method of Indentation)方法。通过对多种金属材料进行压入试验和有限元分析,验证了CR-EMI方法和H-EMI方法的有效性与精确性。
It is of considerable engineering significance to obtain parameters of uniaxial material constitutive relationships by using an indentation method for in-service engineering components,small dimensional components and welding structure materials,and it is useful to estimate the indentation hardness parameters of a material by its constitutive relationship.Based on the theory of indentation tests and elastic-plastic finite element analysis(EPFEA) with contact elements,a linear relationship between the energy ratios and yield stresses is obtained,and a cone indenter test method named constitutive relationship based on the energy method of indentation(CR-EMI) is presented to predict such key parameters of constitutive relationships of metallic materials as elastic modulus,yield stress and hardening index.Furthermore,a method is given named hardness based on energy method of indentation(H-EMI) based on the Hollomon constitutive model to forecast the hardness.The validity and accuracy of the CR-EMI method and the H-EMI method are proved by the indentation tests and finite element analyses of several metals.