Method of compacting dry powder into shapes

Abstract

A method of making shaped articles from powders comprises forming a cup mold of an organic polymeric material such as nylon, cellulose acetate, polymethylmethacrylate, polypropylene or polyethylene. The inner surface of the mold corresponds in configuration with the outer surface configuration desired in the shaped article. This mold is placed in a support member and filled with a measured quantity of powder. A plunger composed of a metal having a high specific gravity is placed on top of the powder, and the mold, mold support, powder and plunger combination is positioned in the swing bucket of a centrifugal apparatus where it is subjected to centrifugal force sufficient to achieve the desired degree of compaction of the powder. The mold is then removed and subjected to treatment at a temperature which is sufficient in the first instance to eliminate the polymeric mold material, as by melting or burning, and then sufficient to sinter the powder. If desired, the surface of the plunger making contact with the powder may be shaped so as to provide a pattern on the powder surface, or to impart a chamfered surface to the powder.

Dependencies are inferred from the claim text.