Fracture mechanisms of fiber-reinforced titanium alloy matrix composites Part II: Tensile behavior

Abstract

The mechanical properties and deformation mechanisms of several unidirectional SCS-6 fiber-reinforced titanium alloy matrix composites under tensile loading were studied. Three different titanium alloys were used as matrix materials: Ti6Al4V, Ti15V3Al3Sn and Ti25Al10Nb. The key microstructural parameters which dominate the stress-strain response, damage initiation, damage growth and fracture behavior of the composites were identified. The strength and Weibull modulus of the interfacial reaction layer as a function of its thickness were also quantified. Finally, the tensile fracture mechanisms near the interface region were classified on the basis of the ratio of fiber strength (σ f) to interfacial shear strength (> i) vs. matrix toughness.