HOT ROLLED STEEL SHEET AND METHOD FOR PRODUCTION THEREOF

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FIELD : metallurgy. SUBSTANCE : invention relates to metallurgy. To provide low-temperature impact strength and high capacity for flanging by controlling structural fraction and difference in hardness between structures of high-strength hot-rolled sheet contains, wt% : C from 0.01 to 0.2; Si from 0.001 to 2.5 or less, Mn from 0.10 to 4.0 or less, P : 0.10% or less, S less than 0.03, Al from 0.001 to 2.0, N less than 0.01, Ti from (0.005 +48/14 [N] +48/32 [S]) or more up to 0.3 or less, Nb from 0 to 0.06, Cu : from 0 to 1.2, Nickel from 0 up to 0.6, Mo from 0 to 1, V from 0 to 0.2, Cr from 0 to 2, Mg from 0 to 0.01 , Ca from 0 to 0.01, Rare-Earth Metals from 0 to 0.1, and B : from 0 up to 0.002, and has texture in central part of sheet thickness, located from surface at distance from 5/8 to 3/8 of plate thickness, in which average ratios of statistical x-ray intensity groups orientations {100} to {223} of plate plane is 6.5 or less than, and ratio of statistical x-ray intensity orientation of crystals {332} is 5.0 or less and microstructure, wherein fraction of total surface area of tempered martensite, martensite and lower bainite is more than 85%, and average diameter of crystalline grains makes 12.0 mqm or less. EFFECT : ensuring provision of low-temperature impact strength and high capacity for flanging. 12 cl, 5 tbl