抄録
Axial loading fatigue tests had been conducted using friction stir welded Al-Mg-Sc alloy and the effect of welding conditions on the fatigue behavior was investigated. The fatigue strengths were insensitive to the welding conditions due to the high heat stability of Al_3Sc hardening precipitates. Fatigue crack initiation locations were dependent on the stress levels irrelevant to the welding conditions. The dependence on the stress levels could be attributed to the transition of fatigue crack initiation mechanism.
