2016 年 1 巻 p. 131-136
In this study, extremely low cycle fatigue tests were performed on an aluminum alloy A6061-T6 subjected to thermal history ranging from 300℃ to 500℃, using U-notched and Hourglass cylindrical specimens respectively. The tests were undertaken under two-step strain control fatigue condition. The results are discussed in terms of effect of thermal history on the fatigue life and residual fracture ductility. The residual fracture ductility is influenced by thermal history, total strain range and cycle ratio. The fatigue life in two step fatigue is influenced by initiation of surface crack at the notch root and the thermal history.
