摘要 |
A multi-phase steel which in addition to iron and unavoidable impurities includes (in % wt.) C: 0.14-0.25%, Mn: 1.7-2.5%, Si: 1.4-2.0%, Al: <0.1%, Cr: <0.1%, Mo: <0.05%, Nb: 0.02-0.06%, S: up to 0.01%, P: up to 0.02%, N: up to 0.01% and optionally one of Ti, B, and V according to the following stipulation: Ti: @0.1%, B: @0.002%, V: @0.15%. A cast semi-finished product, is hot rolled starting at an initial temperature of 1100-1300° C. and ending at a final temperature of 820-950° C., coiled at 400-750° C., cold rolled into the cold flat product at degrees of 30-80%, and subjected to a heat treatment including continuous annealing at 20° C.+Ac1-Ac3 and overageing at 350-500° C.
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