A Comprehensive Approach to Understanding the Influence of the Fiber/Matrix Interface on the Properties of SiC Fiber/Ti-Alloy Composites

Unidirectionally reinforced titanium matrix composites (TMCs) have significant potential to replace more dense materials in future aerospace applications; however, their current low transverse strength motivates the development of new interface systems. To guide the selection of an optimum interface, a comprehensive approach to the characterization of the effect of the fiber-matrix interface on the composite properties must be developed. In the present work, simplified test techniques using microcomposite specimens to investigate the interface influence on the fiber strength and the transverse tensile, longitudinal tensile, and fatigue crack growth behavior of the composite are discussed. These techniques have been successfully employed to understand the role of the interface on the composite properties of interest and have significant promise for future interface development studies. This work was done with titanium alloy Ti-6Al-4V and SiC fibers SCS-0 and SCS-6.