Prepn. of moulded bodies from permeable composite materials - by impregnating porous base metal framework with silver@- or copper@- based alloy

摘要

Mfr. of moulded bodies (I) from permeable composite materials by impregnating a porous base metal framework of tungsten (carbide) or molybdenum (carbide) with a silver- or copper-based alloy as impregnating metal at a temp. above the m.pt. of the silver- or copper-based alloy comprises processing the powdered base metal with 5-40 vol.% thermoplastic to form a flexible moulded body, bringing it into contact with a foil of the impregnating metal or a flexible moulding of the powdered metal and plastic and heating to the impregnating temp. at which the plastic residue-free thermally decomposes or plasticises. Pref. the synthetic material is ethylene-vinyl acetate copolymers, ethylene-propylene copolymers or butyl rubber. The moulded body contains 5-40 vol.% free pores. The moulding is placed on a contact support and soldered onto it at the impregnating temp. USE/ADVANTAGE - (I) are used in electrical contacts. An equal pore-distribution in the base metal framework is obtained and the complicated powder press process is avoided.