A method for manufacturing TMCP heavy plate using soft reduction

摘要

Humul TMCP steel is provided a manufacturing method using the soft reduction (Soft Reduction).; The present invention, in weight%, C: 0.06 ~ 0.11%, Si: 0.20 ~ 0.50%, Mn: 1.30 ~ 1.50%, P: 0.020% or less, S: 0.005% or less, Al: 0.015 ~ 0.050%, Nb: 0.005 ~ 0.025%, Cu: 0.1 ~ 0.2%, Ni: 0.1 ~ 0.2%, Ti: 0.005 ~ 0.015%, N: 50ppm or less, comprising: providing a steel composition with the balance being Fe and other unavoidable impurities; After the steps of the continuous casting of molten steel in the continuous casting machine to the composition of the cast slab soft reduction to 2.43mm preparing a steel slab; After air-cooling the steel slab to room temperature, the, step of re-heating to a temperature of 1050 ~ 1150 ℃; After a cup of reduction rate of the steel slab reheating completing the first ever rolled at 780 ~ 850 ℃ to be 45%, followed by steps to complete the second ever rolled at 720 ~ 780 ℃; It relates to a yield strength of 350Mpa class humul TMCP steel producing method including a; and wherein the step of rolling the steel sheet was cooled to a temperature range of 500 ~ 580 ℃ air cooling.; TMCP, after muljae, soft reduction, the idea rolling