Characteristic S-N property of high strength steels in ultra-wide life region under rotating bending

In order to clarify fatigue properties of high strength steels in the ultra-wide life region, fatigue tests were performed for typical steels SUJ2 and SCM435 using a multi-type cantilever rotating bending machine. The effect of surface finishing on the fatigue property was also examined. Based on the fatigue test data and SEM observation, fatigue behaviors of the respective steels were compared with each other. Thus the fatigue property required for the long life design of mechanical structures was given from a viewpoint of "Eco-Design".