Study of Microstructural Evolution of Press Hardening Steels using Dilatometer and In-situ Studies for a Simulated Hot Stamping Condition

Abstract Press hardening grades are widely used in automotive industries for safety-critical structural parts due to their unique combination of high strength, excellent formability, and crash performance. Considering various scenarios on thermo-mechanical profiles different hot stamping lines, achieving the targeted strength ductility / fracture strain hot-stamped is still challenging some stampers grades. In this investigation, a dilatometer study Usibor®1500 two emerging Usibor®2000 Ductibor®1000 under given condition was conducted with consideration entire hot-stamping processes (i.e., austenitization, blank transfer, forming final quenching from 700°C) understand differences critical cooling rates, evolution microstructures. Influence large (15%) properties also examined Ductibor®500 by DIL 805 A/D tensile deformation mode. In-situ observation microstructural during process explored using Confocal scanning laser microscope uncover physical phenomena further refinement practices.