| 摘要 |
PURPOSE:To obtain the hot dipping steel sheet having a good sticking property by a less flux sticking quantity, by making Zn, Ni or Cu plating layer on the sheet prior to coating the flux before carrying out hot dipping of difficult plating sheet containing easy oxidizing element. CONSTITUTION:Plating layer of Zn, Ni or Cu is made by each method of electric plating, vacuum evaporation of non-electrolytic plating etc. on the above mentioned difficult plating steel sheet. On this occasion, the thickness of the plating layer is necessary to make not less than 0.1mu, especially 0.1-10mu. Next, flux, for example, mixed at mol ratio of 3 vs. 7 of ZnCl2 and NH4Cl and diluted with water, is applied on the above plated sheet. Then, hot dipping of Zn etc. is carried out on the sheet coated the flux. As a result, hot dipping sheet having no defect, such as pinhole, non plating and also enable to lower the flux original unit. |
