Some studies on the influence of stress ratio and test temperature on X-ray fractography observations in C45 steel specimens

摘要

This paper deals with additional ¿X-ray fractography¿ observations made on C45 steel, subsequent to the earlier work [K. Rajanna, B. Pathiraj and B. H. Kolster, Fatigue fracture surface analysis in C45 steel specimens using X-ray fractography. Engng Fracture Mech. 39, 147¿157 (1991)]. Fatigue crack: growth tests were carried out at 20°C on CT samples prepared from this steel using different stress ratios (0.1R, 0.5R and 0.7R). Tests were also carried out at different temperatures (¿20°C, 20°C and 115°C) using a stress ratio of 0.1. The fractured surfaces were analysed for their residual stress state. The influence of the test conditions on the residual stresses developed is discussed.