A novel approach to intermetallic matrix composite (IMC) processing

Intermetallic matrix composite (IMC) precursors including FeAl/Al2O3, FeCrAlY/Al2O3 and NiAl/Al2O3 have been fabricated using a unique processing route which infiltrates multistrand fiber tows with intermetallic powder. Composites processed accordingly are characterized by an intimate distribution of fibers within the matrix material without significantly damage to the fibers. This process involves the collection of data on the surface potential and particle size vs. pH for each material. These data, together with other material constants, are input into a previously developed computer program, Suspension Stability®, yielding the suspension conditions under which the IMC mat may be processed satisfactorily. Specifically, the processing parameters have been adjusted to provide conditions in which the matrix-fiber interaction is unstable (to promote coating of the fiber by the particles in suspension). Details of the experimental parameters of this process are presented, together with microstructural evidence of the infiltration process.