METHOD OF MANUFACTURING MOLTEN ZINC PLATED STEEL PLATES HAVING FEW UNPLATED PORTIONS.

摘要

A method of manufacturing molten zinc plated or alloyed molten zinc plated steel plates having few unplated portions is provided, which has the steps of heating and anneal-reducing a steel plate continuously, and then introducing the resultant steel plate into a molten zinc bath with the steel plate kept not in contact with the atmospheric air to carry out a zinc plating operation, characterized in that a steel plate containing not more than 1 % by weight of carbon, 0.01-1.0% by weight of silicon, 0.05-2.0% by weight of manganese and not more than 0.15 % by weight of phosphorus and satisfying the formula (1): Si/28 + Mn/55 + P/31 >/= 0.01, is used as a material to be plated, this steel plate being subjected to carburization during the anneal reduction thereof or during a period of time in which the anneal-reduced steel plate is being introduced into a molten zinc bath. In formula (1), each element symbol indicates the content (weight percent) of an element of a steel plate).