High temperature low cycle fatigue properties of a HF30-type cast austenitic stainless steel

This work investigated the high temperature low cycle fatigue behavior of HF30-type, cast austenitic stainless steel. In addition to the preliminary results from tensile and thermal expansion tests, isothermal strain controlled fatigue tests at 600 °C and 800 °C were carried out with a total strain amplitude from ±0.20 % to ±0.65% and with a strain rate of 10−3/s. The plastic strain amplitudes during cyclic strain loading were measured and correlated with the fatigue lifetime using Coffin–Manson plots at each test temperature. These plots were re-constructed into a general superposition curve containing the results from both temperatures using a constitutive equation of the energy criterion for fatigue failure in terms of thermally activated dislocation motion. The cast and wrought stainless steels showed similar fatigue properties.