Scott J Jankowski, 62737 Littletown Rd, Gladwin, MI 48624

4834938, May 30, 1989

Apr 25, 1988

7/185678

Aleksander J. Pyzik - Midland MI
Jack J. Ott - Hemlock MI
Scott J. Jankowski - Midland MI

The Dow Chemical Company - Midland MI

B22F /00

419 6

A process is described for making a composite article without shrinkage, particularly of ceramic and metal wherein the article includes complex internal surfaces or cavities. The process requires forming an insert body that includes an external surface that corresponds to an internal cavity of the article. The insert body consists of a material having a melting temperature less than that of the article. The process further requires forming a porous compact about the insert body wherein the compact is formed into the substantially the net shape of the article. The compact is made of a material that is wetted by liquid insert material and has a sintering temperature greater than the wetting temperature of the insert material. The process further requires heating the article to a temperature such that the inserts substantially melts and infiltrates the porous compact forming the finished composite article. The process produces products including complex internal surfaces without the necessity of costly and sometimes technically difficult internal machining operations.