TENSILE TEST BASED MATERIAL IDENTIFICATION PROGRAM AFDEX/MAT AND ITS APPLICATION TO TWO NEW PRE-HEAT TREATED STEELS AND A CONVENTIONAL Cr-Mo STEEL

Abstract

A material identification program AFDEX/MAT is presented in this paper. The program is based on the method for acquiring true stress-strain curves over large range of strains using engineering stress-strain curves obtained from a tensile test coupled with a finite element analysis. In the method, a tensile test is analyzed using a rigid-plastic finite element method combined with a perfect analysis model for its associated simple bar to provide the information of deformation. An initial reference true stress-strain curve, which predicts the necking point exactly, is modified iteratively to minimize the difference in tensile force between the experiments and predictions of the tensile test. It was applied to identifying the mechanical behaviors of two new pre-heat treated steels of ESW95 and ESW105 and a conventional Cr - Mo steel of SCM435. The predictions are compared with the experiments for the tensile test of the three materials, showing an excellent similarity.