Abstract
In order to use a low flammability magnesium alloy as structural components, very high cycle fatigue property of this alloy (AMCa602) was investigated in rotating bending. As results, it was found that some specimens failed from surface inclusions and their fatigue lives were lower in comparison with those of the specimens without surface inclusions. And, the fracture surfaces of this alloy revealed very rough in the usual life region, whereas a smooth area was observed on the fracture surface of specimens failed from surface inclusions in gigacycle regime. A stress intensity factor range at the tip of the smooth area tended to a definite value so that the fracture mechanism of this alloy was governed by a concept of ΔK.
