Journal Archive

When a metallic powder is subjected to a sufficiently high pressure a certain amount of adhesion takes place between individual particles. If this compact is then sintered the bond is improved by diffusion and intergranular grain growth. The earliest known platinum objects were fabricated by such a powder metallurgical process, and when European scientists first addressed the problem of manufacturing platinum bars they also used powder metallurgy to overcome their inability to melt the metal. Now powder metallurgical methods are widely used for fabricating a variety of materials, and this paper reviews studies made of the sintering of refractory metals when this process is promoted by the addition of a minor amount of a platinum group metal activator.