Elucidating the effects of cold rolling route on the mechanical properties of AISI 316L austenitic stainless steel

Abstract

The evolution of mechanical properties of an AISI 316L austenitic stainless steel was studied during cold rolling via unidirectional and cross-rolling routes. It was shown that the low thickness reduction of 25% in cross-rolling leads to the formation of greater amounts of strain-induced martensite (based on the transformation-induced plasticity effect) and higher dislocation density, leading to a remarkable combination of transformation strengthening and work hardening effects. At the high thickness reduction of 75%, while the strengthening effects of both rolling routes became comparable, cross-rolling resulted in a less pronounced directionality of mechanical properties. In this regard, an alternative method for the evaluation of anisotropy in the cold rolled sheets (based on the obtained values of ultimate tensile strength for tensile samples prepared in different directions) was proposed. Accordingly, it was demonstrated that cross-rolling has a high potential for the enhancement of mechanical properties at low thickness reductions, preservation of equiaxed structure even at high thickness reductions, and decreasing of anisotropy and directionality of properties compared to the unidirectional rolling.