| 摘要 |
PURPOSE:To obtain a product with high enameling hardenability as well as high workability and high delayed ageability at ordinary temp. by heating a steel plate to a specified temp. in a line other than a galvanizing line after galvanizing or alloying to partially precipitate carbon. CONSTITUTION:A steel plate consisting of, by wt., 0.005-0.1% C, <=0.4% Si, 0.08-0.8% Mn, <=0.1% sol. Al, <=0.01% N and the balance Fe with inevitable impurities while satisfying soln. Al/N>2 is heated to 120-320 deg.C and held at the outside of a galvanizing line after galvanizing or alloying to partially precipitate carbon. When the temp. is below 120 deg.C, partial precipitation of carbon is difficult in the scale of practical operation. When the temp. exceeds 320 deg.C, carbon is thoroughly precipitated, and enameling hardenability due to residual solubilized carbon cannot be expected. |
