MIXTURE FOR PROCESS PRECOAT OF CERMET ELECTRIC CONTACTS Russian patent published in 1995 - IPC

FIELD: powder metallurgy. SUBSTANCE: mixture for process precoat of electric contact with working layer of silver-containing material contains powder of nonprecious metal taken from group including copper, nickel, and additionally formate Me(HCOO)₂ taken from group including iron, cobalt, nickel or copper in the amount of 2-10 mas.% in terms of acid residue HCOO. Mixture for process precoat is produced by mixing, in particular, copper powder and copper formate powder for, e.g., 30 min. rubbing through sieve and drying. Mixture is filled into mold, then, mixture of working layer is filled and pressed to obtain bimetallic intermediate product. Contacts are produced by sintering and final pressing. EFFECT: higher strength of adhesion of precoat with working layer. 4 tbl