| 摘要 |
PURPOSE:To prevent the electric corrosion of a joined part by joining gold or a gold alloy to stainless steel with an Ni layer as an insert in-between, diffusing the Ni in the metals on both sides by heat treatment, and quenching the joined part to carry out soln. heat treatment. CONSTITUTION:A stainless steel base 3 for a wrist watch is coated with an Ni layer 2 of about 2mum thickness by plating, and a gold or gold alloy plate 1 is joined to the layer 2 by diffusion. The Ni 2 layer is diffused in the plate 1 and the base 3 by heat treatment, and the joined part is quenched from 700-1,200 deg.C to carry out soln. heat treatment. The surfaces of the plate 1 and the base 3 are then polished as one body to provide a mirror finished surface 4. |
