Abstract
The effect of multiple hot rolling in the temperature interval of 700-1000°C (1290-1830°F) on microstructures and tensile behavior of an S304H-type austenitic stainless steel was studied. The structural changes during hot working are characterized by the elongation of original grains towards the rolling axis and the development of new fine grains. The fraction of fine grains and the average grain size increase with increasing the rolling temperature. The multiple hot rolling results in significant strengthening. The offset yield strength approaches 1080 MPa in the sample processed at 700°C (1290°F), while that of 390 MPa is obtained after rolling at 1000°C (1830°F). On the other hand, the tensile strength at elevated temperatures of 600-700°C (1110-1290°F) decreases with a decrease in the rolling temperature. The relationship between the deformation structures and the tensile behavior is considered in some detail.