Heat Criterion of the Change of Strain-Hardening Stages in Austenitic Stainless Steel

Resumo

The infrared thermography method was used to study changes in the temperature of austenitic stainless steel in the process of tensile deformation. It was revealed that the temperature of the sample stops growing in the transition region between the linear stages of strain hardening. This phenomenon can be connected with a change in the entropy of the deformed medium as a result of a reconstruction of the ordered autowave structures. In the region of true deformation exceeding 0.4, a phenomenon of discontinuous flow (Portevin–Le Chậtelier effect) is observed, which is accompanied by the motion of the single fronts of localized deformation. The observed fronts are heat sources, and the value of the temperature at the arbitrary point of the sample is determined by its position relative to the front of deformation.