Experimental in-situ verification of the unloading mechanics of dual phase steels

The paper presents the first experimental verification of dislocation repulsion during springback of Dual Phase (DP) steel, a mechanism which is suggested to cause non-linear unloading due to micro-plastic strain generation. In-situ loading-unloading tests are conducted within a Scanning Electron Microscope (SEM). It is shown that strain partitioning between ferrite grains as well as within a single ferrite grain occurs. It was observed that...