The resistance the cold rolled carbon steel sheets for vitreous enameling and the production manner null which are superior in mark bi Characteristic, resistance bubble black spot defective Characteristic and press

摘要

PURPOSE:To obtain the steel sheet having good press formability and fishscale resistance as well as excellent porcelain enameling characteristics by subjecting a steel slab in which compsn. is limited to a specified range to hot rolling, to cold rolling at a specified rolling reduction and thereafter executing continuous annealing at a specified temp. CONSTITUTION:A steel slab having the compsn. constituted of, by weight, =0.0025% C, =0.50% Mn, 0.007 to 0.020% B, 0.01 to 0.07% Cu, =0.010% Al, 0.008 to 0.020% O, 0.005 to 0.020% N, =0.020% P and the balance Fe with inevitable impurities is manufactured. The steel slab stock is hot-rolled and is cold-rolled at =70% draft. After that, the stock is subjected to continuous annealing at the heating temp. of 800 deg.C to the Ac3 transformation point or below. If required, one or both of =0.050% Ti and to =0.050% Nb is incorporated into the above steel. Or, 0.0001 to 0.100% Se is furthermore substituted for the same quantity of Fe. The steel sheet has excellent foaming resistance and resistance to the defect of black spots as well as excellent porcelain enameling characteristics such as adhesiveness in porcelain enameling.