FE-NI ALLOY OR FE-NI-CO ALLOY HAVING SUPERIOR HEAT RESISTANCE IN NOBLE METAL PLATING

摘要

PURPOSE:To improve the heat resistance of an Fe-Ni or Fe-Ni-Co alloy during noble metal plating by regulating the work degenerated surface layer of the alloy to a thin layer of a specified thickness. CONSTITUTION:An Fe-Ni or Fe-Ni-Co alloy ingot is hot rolled, cold rolled and subjected to cold rolling including annealing. The thickness of the work degenerated surface layer is regulated to <=5mum by selecting conditions during the final cold rolling and the kind of lubricating oil used. When the alloy is plated with a noble metal at a high temp., the resulting plating does not tarnish because the alloy has superior heat resistance.