Activated twinning variant determination in cold-rolled 316L stainless steel by effective Schmid factor analysis

Abstract

A method is proposed to determine accurately the activated twinning variant during the cold-rolling of 316L stainless steel parts produced by L-PBF (Laser Powder Bed Fusion) from EBSD datas. The twinning variant selection is carried out by Schmid factor (SF) computations, using an effective Schmid factor for cold-rolling specifically. Schmid factor was proven to be a relevant parameter to predict the experimentally activated twinning variant. Additionally, cold-rolling deformation is shown to be composed by a strong compression component, along with a minor traction component. The effective Schmid factor is then modified accordingly to ensure a better prediction of twinned grains. Moreover, twinning Schmid factor analyses in traction and compression provide valuable information on the twinning activation regarding textured materials such as L-PBF 316L steel.