| 摘要 |
PURPOSE:To manufacture a high Cr ferritic steel having improved weldability by hot working and tempering a high Cr ferritic steel contg. specified percentages of C, Si, Mn, Cr, Ni, Mo, V, Nb, Al and N. CONSTITUTION:A high Cr ferritic steel contg., by weight, 0.05-0.15% C, <=0.50% Si, <=1.5% Mn, 8.0-12.0% Cr, <=1.0% Ni, 0.8-1.3% Mo, 0.01-0.3% V, 0.01-0.30% Nb, <=0.20% Al and 0.005-0.10% N is hot worked and tempered to obtain a high Cr ferritic steel having improved weldability. In order to improve the Charpy impact value, the steel is heated to <=about 1,200 deg.C before hot working. In order to improve the creep rupture strength, rolling is preferably finished at about 1,050 deg.C. In order to improve the creep rupture ductility, rolling is finished at >=about 900 deg.C. |
