Orientation Dependence on Fatigue Fracture Behavior in Uniaxial Fatigue Tests of Pure Mg Single Crystals

Abstract

Three Mg single crystalline round bar specimens with different crystal orientations were subjected to uniaxial tension com pression fatigue tests, and the crystal orientation dependence on fatigue fracture behavior was investigated. The loading direction of AD, BC and EF specimens was 1120 , 1100 and 0001 respectively. At stress amplitude σ a over 60 MPa, fatigue life of BC specimen was longest and fatigue life of EF specimen was shortest. When the stress amplitude was 20 MPa, fatigue lives of all specimens were almost the same. Our study suggested that fatigue life in Mg single crystals show high dependence of crystal ori entation and stress.