CREEP FATIGUE INTERACTIONS IN A 1 Cr Mo V STEEL - 1.

Static and cyclic creep tests have been carried out on a 1 Cr Mo V steel at 565 degree C. The effects of prior high strain fatigue on subsequent creep behavior is studied. A well defined ductile/brittle transition was noted which was unaffected by the type of load controlled cycle. The material softened under cyclic plastic strain and no experimental evidence was obtained which indicated that fatigue and creep damage interacted in a load controlled test to give rise to unexpectedly short lives. The conclusion derived is that ″softened creep″ data should be used in predictions of deformation and rupture behaviour, and that the use of virgin creep data can give rise to substantial errors.