EBSD study of micromechanisms involved in high deformation ability of DP steels

Abstract

Notched and un-notched tensile specimens of fine grained commercial DP780 steel were deformed in uniaxial tension until fracture. Micro-texture analysis was performed by using an FE-SEM equipped with an EBSD detector and the data were analyzed to quantify orientation gradients within the microstructure of the deformed specimens in terms of Image Quality, Inverse Pole Figure and Taylor Factor map. High deformation ability of DP steels was found to be mostly due to such mechanisms as grain rotation, void creation and evolution, substructure formation within the ferrite grains and the highly plastic stretching of martensite during the deformation process. The true strain of martensite was measured up to 64% and 74% for the un-notched and notched specimens, respectively. (C) 2015 Elsevier Ltd. All rights reserved.