Stress affected transformation in low alloy steels – factors limiting prediction of plastic strains

The present study identifies key material phenomena that limit the predictive capabilities of current approaches employed in modelling heat treatments of steels. Focus is on aspects relating to isothermal transformation in low alloy steels. Specifically, experimental data are presented relating to the effects of small plastic deformation on the kinetics of the phase transformation and on transformation plasticity. In addition, stress-strain response of supercooled austenite prior to transformation, i.e. in the temperature range between the A3-temperature and the martensite start temperature, has been determined experimentally. The data obtained demonstrate that the experimental results are only partially compatible with assumptions made in current models that are employed in modelling of heat treatments of steels