SIMULATION OF MICROSTRUCTURAL EVOLUTION DURING TMC MONOTAPE CONSOLIDATION PROCESSING

The consolidation of fiber-reinforced titanium matrix composite (TMC) monotapes produced by spray deposition is an important step in the man ufacture of TMC components. The performance of this class of composite s is controlled by fiber-matrix properties and by the composite's rela tive density, fiber microbending stress/fracture and by the interfacia l reaction layer thickness at the fiber-matrix interface after process ing. These three microstructural features evolve during consolidation processing. Models for predicting the microstructure's dependence upon process conditions (i.e. the lime varying pressure and temperature) a re combined with consolidation equipment dynamics to simulate the micr ostructural evolution and to assess the relative ''processibility'' of several silicon carbide fiber-titanium alloy matrix systems during th eir transient consolidation processing. The dependence of the microstr uctural state upon the material system's mechanical properties and the monotape's initial geometry has also been investigated and is used to propose guidelines for the selection of TMC system materials and mono tape geometry parameters.