| 摘要 |
<p>A method of hot-dip-zinc-plating a Si, Mn or Cr-containing high-strength and high-tension steel plate as a basis steel plate reduced in unplated portions, so as to produce a hot dip zinc-plated steel plate or a hot dip alloyed zinc-plated steel plate, characterized in that the method is capable of minimizing the complication of a process and a decrease in the productivity and producing at a low cost high-quality hot dip zinc-plated steel plates. The present invention can be effected by recrystallization annealing in a continuous annealing equipment a cold rolled steel plate containing at least one of not less than 0.1 wt% and not more than 2.0 wt% of Si, not less than 0.5 wt% and not more than 2.0 wt% of Mn and not less than 0.1 wt% and not more than 2.0 wt% of Cr, and not more than 0.2 wt% of P as necessary; cooling the annealed product; removing a concentrated layer of steel components in a steel plate surface by polishing, or pickling, or a combination of polishing and pickling; and thermally reducing the steel plate in continuous hot dip zinc plating equipment at not less than 650 °C and not more than a recrystallization temperature, whereby the hot dip zinc plating, or the top plating and/or alloying, or, additionally, the post-alloying top plating of the steel plate is done.</p> |
