The fatigue life of 42CrMo4 steel in the range of HCF to VHCF at elevated temperatures up to 773 K

Abstract The fatigue lives of forged and cast 42CrMo4 steel were investigated in the range from high- up to very high cycle fatigue. The experiments were performed at 295 K (RT) and elevated temperatures of 473 K and 773 K. The fatigue failure occurred due to internal defects (non-metallic inclusions and microshrinkages). The results were discussed according to the influence of temperature and internal defects on the fatigue behaviour. The fatigue lives at 773 K were described using a short crack growth model and it is shown that the damage mechanism changed from lower temperatures to 773 K.