Mechanism-controlled thermomechanical treatment of high manganese steels

Austenitic high manganese steels exhibit outstanding mechanical properties, such as energy absorption, owing to various deformation-mechanisms dislocation slip, twinning-induced plasticity (TWIP) and transformation-induced (TRIP). Here, we show a novel thermomechanical treatment manufacture steel Fe–18Mn-0.3C (wt.-%) with excellent performance by combining these three deformation-mechanisms. This process of mechanism-controlled rolling resulted in ultra-high tensile strength the up 1.6 GPa, simultaneously uniform elongations 15%. A was developed establish this combination properties. Warm conducted at 200 °C, suppress TRIP activate TWIP deformation mechanism. Thus, density twins dislocations introduced microstructure, avoiding martensite formation. During subsequent recovery annealing 520 °C or 550 reduced, yet preserved. The warm an ultrafine microstructure moderate dislocations. effect is predominant during plastic ambient conditions highly twinned microstructure. resulting exhibits yield sufficient ductility, favorable properties for lightweight construction automotive aerospace industry.