| 摘要 |
PURPOSE:To produce titled high tensile steel by forming molten steel contg. specific contents of C, Si, Mn, P, S, Nb, B, solAl and contg. P, C, Mn in specific relations to an ingot by continuous casting or large sized steel ingot-blooming stages and hot rolling the ingot. CONSTITUTION:Molten steel is composed, by wt% of 0.002-0.15 C, 0.1-1 Si, 0.5-2.5 Mn, <0.03 P, <0.005 S, 0.01-0.12 Nb, 0.0002-0.005 B, 0.01-0.005 sol Al, and the balance Fe and unavoidable impurities wherein the contents of P, C, Mn are so controlled as to satisfy the formula. After such molten steel is formed into an ingot by continuous casting or large sized steel ingot-blooming stages, the ingot is hot rolled. If necessary, the steel is subjected to accelerated cooling or heat treatments. |
