Low cycle fatigue of GX12CrMoVNbN9 -1 cast steel at 600°C temperature

摘要

The paper treats of the low cycle fatigue (LCF) behaviour of GX12CrMoVNbN9-1 (GP91) cast steel after heat treatment. Fatigue tests at the temperature of 600°C within the scope of small amount of cycles to failure were carried out for five levels of controlled amplitude of total strain ε_(ac) = 0.25, 0.30, 0.35, 0.50 and 0.60%. The investigated cast steel within the scope of low cycle fatigue life reveals a three-stage course of changes in strength and strain. In the given scope of low cycle fatigue for GP91 cast steel, cyclic weakening was observed without the occurrence of stabilization period of its properties.