Surface Relief Evolution in 316L Steel Fatigued at Depressedand Elevated Temperatures

摘要

Surface relief of austenitic 316L steel cycled with constant plastic strain amplitude at depressed and elevated temperature was studied using scanning electron microscopy and atomic force microscopy. The formation of PSMs and their evolution during cycling was followed. PSMs consist primarily of extrusions accompanied later by parallel intrusions. The kinetics of the early intrusion growth was assessed. At the lowest temperatures only static extrusions and intrusions were Pound. The findings were discussed in relation to point defect models of fatigue crack initiation