| 摘要 |
PURPOSE:To roll a weather-resistant steel having a specified composition contg. Cu without causing hot tear crack by adding a proper amount of Si to the steel and restricting the heating and rolling temps. during rolling. CONSTITUTION:A steel contg. <=1.0% C, 1.0-2.0% Si, 0.1-2.0% Mn, <=0.15% P, 0.01-0.10% Al and 0.2-2.0% Cu as essential components and 0.01-0.2% one or more among Nb, V, Ti and Zr or further contg. <=1% Cr and/or Mo, <=0.15% Ca or rare earth element and <=100ppm B is heated at <=1,150 deg.C and hot-rolled at the Ar1 point-1,150 deg.C. The steel may be heated at >=1,150 deg.C, regulated to <=1,150 deg.C rolling start temp., and hot rolled at the Ar1 point-1,150 deg.C. |
