| Summary: | 碩士 === 國立臺灣海洋大學 === 材料工程研究所 === 93 === The aim of this work is to study the effect of cold work on hydrogen embrittlement and mechanical in AISI 403 stainless steel. Hydrogen embrittlement of as received, 10% and 20% cold worked AISI 403 stainless steel has been evaluated by using electrochemical permeation measurement and tensile test in this study.
For electrochemical permeation measurement, it is known that hydrogen effective diffusivity and permeation rate increase with increase cold work. Cold may cause some micro-crack in microstructure, thus resulting in the high rate of hydrogen permeation.
For slow train rate tests, the ultimate tensile strength increase with the amount of cold work, while elongation decrease with cold work. After hydrogen charging, hydrogen diffused into the the microstructure, resulting the elongation decayed significantly. The fractography of precharged specimens shows that the ductile fracture has changed to the brittle fracture, and some hydrogen-assisted secondary cracks were also observed in the specimens.
|
|---|
