| 摘要 |
<p>1477037 Powder metallurgy SIEMENS AG 23 Aug 1974 [13 Sept 1973] 37243/74 Heading C7D Powder mixtures of two or more of Cr, Cu, Fe, Ni, Ti and Zr with Fe, Cu or Ni constituting 35-60 volume % of the mixture, are cold pressed to a porosity no more than 30 volume %, sintered in a protective gas or under vacuum and the sintered body is hot compressed below the melting point of the lowest melting point of any metal present to provide a final porosity of no more than 2 volume % avoiding the formation of a liquid phase during the hot compression. The product may be annealed in protective gas or vacuum, the hot compression may be effected by drop-forging, pressing or extrusion and the composition may be used for contact materials in vacuum switches.</p> |
