Fatigue design factors for ECAPed materials

Equal channel angular pressing (ECAP) was successfully performed on commercial pure aluminum, aluminum 6061 alloy and commercial pure copper by route BC. Tensile and fatigue (under constant stress) tests shows a significant enhancement in mechanical properties consisting of hardness, yield strength, ultimate tensile strength and endurance limit, but the ductility of the alloys reduced with employing this process. Two fatigue design factors Kl and Kh has been suggested to co-related fatigue data from coarse grained (CG) to ultra-fine grained (UFG) materials.