PREPARATION METHOD FOR ELECTRICAL CONTACT MATERIALS

摘要

A preparation method for electrical contact materials comprises the steps: coating colloidal graphite or metallic oxides with a layer of nickel by chemical plating, and then coating with silver so as to form an Ag-Ni-C or Ag-Ni-MeO core-shell structure. Wettability of the interfaces between the colloidal graphite or the metallic oxides and the silver substrate are improved, and adverse impacts on mechanical properties of the electrical contact materials caused by poor wettability of interfaces in conventional powder metallurgy methods are eliminated. More importantly, the silver of intermediate composite particles is replaced by coating with metal nickel; thereby the consumption of silver is reduced. Main roles of coating with silver are improving oxidation resistance of composite particles, sintering and granulation performances, and deformability of the intermediate composite particles in working, thereby improving processing properties.