PROCESS FOR PRODUCING A CuCr CONTACT MATERIAL FOR VACUUM SWTICHEs AND APPROPRIATE CONTACT MATERIAL

摘要

Purely powder-metallurgical or sinter impregnation processes are often used to manufacture CuCr contact materials. Here the aim is to obtain the lowest possible residual porosity, which should be < 1 %. According to the invention, a powder moulding of the components is densified in two stages; the first stage is a sintering process with a densification of the sintered body to a closed porosity and the second stage is a hot isostatic pressing process (HIP) in which the unencased workpieces are taken to a final density amounting to a space occupation of at least 99 %. Thus an economical method of manufacturing high-grade material is obtained. It is possible in particular to produce multi-layer contacts or self-adhesive bonds between the sintered body and a solid substrate, e.g. a copper contact bolt.