Simulation of hot working of austenitic stainless steels
The published literature on the strength and structural changes occurring during and after hot working of AI5I316 and 304 austenitic stainless steels are reviewed. Isothermal plane strain compression tests have been carried out with the purpose of determining relationships to describe the kinetics of static recrystallization, the recrystallized grain size, the isothermal grain growth rate and the strength during hot rolling of AISI316 steel. The kinetics of static recrystallization were also studied in samples tested in axisymmetric compression, or hot rolled. The effect on the kinetics of static recrystallization of the strain distribution in samples tested in plane strain compression was analysed. The set of equations determined for 316 steel wasused in a computer model modified from the one developed by Leduc (1980) for simulation of hot rolling loads and microstructural evolution. Partially recrystallized microstructure was generated in a laboratory hot rolling mill and was reasonably simulated by the use of the computer programme. Non-isothermal plane strain compression tests were carried out for direct simulation of laboratory hot rolling results. Comparison between experimental hot rolling and plane strain compression data has shown reasonable levels of agreement in the microstructural simulations undertaken in the present work. The mean plane strain strengths from non-isothermal plane strain compression tests were higher than the ones from hot rolling. This may have been caused by thermal gradients inside the sample being tested.