Evaluation of Tensile Properties affected by Diffusible Hydrogen in High Strength Steels

Abstract

The evaluation of delayed fracture which is a kind of hydrogen embrittlement is required when high strength steel sheets are applied to automobile structures to reduce the weight and the fuel consumption. SSRT, Slow Strain Rate Technique, and CLT, Constant Load Test, are often used to evaluate bolt steels. In this study, we applied SSRT and CLT to evaluate a martensitic steel sheet. These tests were carried out under cathodic hydrogen charging with NaCl solution. As a result, quantitative relationship between diffusible hydrogen content and tensile strength was obtained by SSRT and CLT. There are little difference between these experimental methods.