Simulation of microstructural evolution during TMC monotape consolidation processing

Abstract

The consolidation of fiber-reinforced titanium matrix composite (TMC) monotapes produced by spray deposition is an important step in the manufacture of TMC components. The performance of this class of composites is controlled by fiber-matrix properties and by the composite's relative density, fiber microbending stress/fracture and by the interfacial reaction layer thickness at the fiber-matrix interface after processing. These three microstructural features evolve during consolidation processing. Models for predicting the microstructure's dependence upon process conditions (i.e. the time varying pressure and temperature) are combined with consolidation equipment dynamics to simulate the microstructural evolution and to assess the relative “processibility” of several silicon carbide fiber-titanium alloy matrix systems during their transient consolidation processing. The dependence of the microstructural 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 monotape geometry parameters.