抄録
fatigue crack growth and the threshold of SS41, SM41A, and SUS304 steels and 2218-T6 Al alloy were examined at elevated temperatures up to 500°C. An emphasis was made on examining the role of crack closure in the fatigue threshold at elevated temperatures. Fatigue threshold, ΔKth, was found to increase with an increase in test temperatures for all the steels tested, while it was found to decrease for the 2218-T6 Al alloy. Oxide-induced crack closure was found to play an important role in the temperature dependence of ΔKth for SM41A and 2218-T6 Al alloy, while it was found to play a less important role in the increase in ΔKth at elevated temperatures for SS41 and SUS304 steels. The importance of the relative value of the oxide thickness to the CTOD at threshold was discussed.
