Sintered metal powder electric contact material

摘要

An electric contact material comprises a matrix formed by refractory metal powder particles having interbonding portions and defining pores infiltrated by a solidified molten metal impregnant. The interbonding portions are formed by a solidified molten alloy formed by the refractory metal and an alloying metal, and has a melting temperature above the impregnant's melting temperature. The alloying metal is present in an amount that is small relative to that of the refractory metal but which is effective for the formation of the interbonding portions by the alloy. The material may be made by cold molding the refractory metal powder particles and powder particles of the alloying metal, to form a compact which is then sintered without being under pressure. The interbonding alloy forms during the sintering, and when solidified, forms the interbonding portions between the particles defining the pores. By infiltration these portions are filled with the molten impregnating metal.