| 摘要 |
PURPOSE:To produce an Al hot-dipped steel plate of superior tensile strength and cold formability by subjecting a steel strip of the composition consisting in adding a suitable amount of Ti to a base steel of low C-Si-Mn-Cr system to heat treatment under specific conditions then dipping the same in an Al-Si hot dipping alloy bath. CONSTITUTION:A steel slab contg. 0.03-0.12% C, 0.05-0.30% Si, 0.20-0.60% Mn, 0.10-0.50% Cr, 0.03-0.20% Ti and <0.05% Sol.Al is heated to >=1,150 deg.C, and is hot-rolled at the finishing temp. of >=830 deg.C, thence it is coiled at the temp. of <=630 deg.C. Next, it is cold-rolled at >=40% draft and is annealed at 850-950 deg.C in a continuous Al plating production line. This is dipped for the time within 20sec in a molten bath of Al-Si of <13% Si, whereby the Al hot-dipped steel plate of >=41kg/mm.<2> tensile strength and superior cold formability is produced. |
