High Energy-Rate Forming of Fibrous Composites

Fabrication problems with metal matrix composite materials include compatibility of the matrix and reinforcement, retention of fiber alignment, and formation of intricate shapes or structures. Preliminary studies of eleven composite systems were made at Battelle-North-west using a pneumatic-mechanical high energy-rate forming process. Compatibility problems were reduced by the use of lower temperatures than those used in more conventional processes. Alignment retention appeared to be controllable by varying the impaction mold design to produce preferential axial, radial, or isostatic forces. The forming method was highly effective for the formation of complex monolithic structures such as turbine blades, honeycombs, and nozzles having internal cooling passages.