P029 Hydrogen Degradation Susceptibility by Slow Strain Rate Technique and Constant Load Test of Cold-Drawn High-Strength Stainless Steel Wire

Abstract

Fuel cell system is greatly expected as a domestic power supply and car motive power to practical use. The spring materials used in this system are exposed to high pressure hydrogen gas environment, so that it is absolutely imperative that the spring materials have high-strength and resistance properties for hydrogen embrittlement. Recently, Slow Strain Rate Technique (SSRT) test is mainly applied as evaluation for hydrogen degradation susceptibility. However, in the real use environment, load condition is mostly not in plastic region, but in elastic region. In the present study, we analyzed hydrogen absorption characteristics and evaluated hydrogen degradation susceptibility using constant load test (CLT) in elastic region ,and SSRT test in plastic region to comparison in cold-drawn high-strength metastable and stable austenitic stainless steel wires.