Excellent formability (成形 性), forming after high artificial aging curing (人工 时效 硬化 性), high strength, low yield ratio (降 伏 比) and high ductility (延性) and with aspects rivers sheet (雨 相 钢 sheet) manufacturing How to

摘要

The manufacturing method steel sheet with a compound structure is composed of winding step after hot rolling annealing step continuously steel sheet and cooling step to less than 200C from annealing temperature. The steel sheet has a compound at least one quenched transition phase selected from a group that consists of ferrite phase, a martensite phase, a bainite phase, and an austenite phase. Also, this steel sheet has the tensile strength above 40 kilogram per square milimeter, the excellent plasticity and the high hardening characteristic by artificial aging.