METHOD FOR PRODUCING A HOT-ROLLED STEEL PRODUCT, AND A HOT-ROLLED STEEL

摘要

The invention relates to a method for producing a hot-rolled steel from a steel, whose composition as percentages by weight is C 0.075 - 0.12% Si 0.1 - 0.8% Mn 0.8 - 1.7% Al 0.015 - 0.08% P less than 0.012% s less than 0.005% Cr 0.2 - 1.3% Mo 0.15 - 0.80% Ti 0.01 - 0.05% B 0.0005 - 0.003% V 0.02 - 0.10% Nb less than 0.3% Ni less than 1% Cu less than 0.5% the rest being iron and unavoidable impurities. The invention relates in particular to direct quenched martensitic sheet-like steels, on which temper annealing is conducted, i.e. tempering steels and their production. The hot-rolled steel according to the invention is exceptionally temper-resistant after the direct quenching process, wherein by tempering it is made further high-strength (Rp0.2=890MPa) combined at the same time with good impact toughness (Charpy V (-20°C) =37J/cm2 ) and flangeability as well as good weldability.