Part 2: Behaviour of a 1 Cr Mo V Steel Subject to Combinations of Fatigue and Creep under Strain Control

Abstract

A 1 Cr Mo V steel has been studied at 565 °C under a cyclic strain axial mode with various combinations of tensile and compressive dwell periods. Compared with the continuously cycled data, the presence of a tension only dwell caused a considerable decrease in the number of cycles to failure. The addition of a compressive dwell to the cycle already containing a tensile dwell tended to reduce or eliminate the harmful effects of the latter. Metallographic evidence suggests that the compressive dwell reduced the incidence of internal intergranular cracking. A ratchetting grain boundary damage model to account for this is proposed.