The Effect of Hydrogen on the Fatigue Behaviour of Dual - Phase Steels
소재령Jae Ryung So, 이경섭Kyung Sub lee
Abstract
The effect of hydrogen on fatigue behaviour of dual phase steels with various martensite morphology and volume fraction was studied. Two different heat treatments, an intermediate quenching and an intermediate air cooling, were employed to change martensite morphology and its volume fraction. Fatigue lifetime in hydrogen was decreased with increase in martensite volume fraction because martensite promoted fatigue crack initiation and propagation in hydrogen. I.Q, heat-treated specimen with fibrous martensite morphology was more sensitive to hydrogen than LA. heat-treated specimen with globular martensite morphology. All of the specimens showed the crack initiation at the martensite-ferrite interfaces and the propagation through both the ferrite and the martensite.