ZN-SN ALLOY PLATING STEEL SHEET WITH AN EXCELLANT CORROSION RESISTANCE, ADHESION AND WORKABILITY AND PROCESS THEREFOR

摘要

The steel sheet having excellent corrosion resistance, adhesion property and workability includes a Zn-Sn alloy vacuum deposited layer of 10-70 g/m2 composed of 10-70 wt.% Zn and 30-90 wt.% Sn. The method for vacuum deposition comprises; (a) placing Zn and Sn vaporising sources charged with respective Zn and Sn in a vacuum chamber; (b) evacuating the vacuum chamber to below 10-5 torr; (c) blowing Ar gas in the vacuum chamber; (d) cleaning a substrate by supplying a negative voltage of 500-1000 V; (e) heating the substrate at room temp. to 250 deg.C; (f) degassing the vaporising sources by introducing a current; (f) vacuum depositing Zn-Sn alloy by opening the covered shutters of the Zn and Sn vaporising sources.