Press forming of a low alloy steel part with an increased ductility region

摘要

A shaped low alloy steel part, having regions of increased ductility, is produced by heating regions of a sheet of the steel to 600-900 deg C in less than 30 seconds, before or after forming and hardening in press tooling. A shaped metal part, having regions of increased ductility, is produced from a sheet of steel of composition (by wt.) 0.18-0.3% C, 0.1-0.7% Si, 1.0-2.50% Mn, /}0.025% P, 0.1-0.8% Cr, 0.1-0.5% Mo, /}0.01% S, 0.02-0.05% Ti, 0.002-0.005% B, 0.01-0.06% Al, balance Fe and impurities by (a) heating regions of the sheet to 600-900 deg C in less than 30 sec. and then forming and hardening in press tooling; (b) press forming the sheet to an intermediate or finished product, heating regions of the product to 600-900 deg C in less than 30 sec. and then post-pressing and/or hardening in press tooling; or (c) heating the sheet uniformly to 900-950 deg C, forming and hardening the sheet in press tooling and heating regions of the sheet to 600-900 deg C in less than 30 sec.