Effect of volume fraction of reinforcement on room temperature tensile property of in situ (TiB + TiC)/Ti matrix composites

In this paper, Ti-1100 composites reinforced with TiB and/or TiC were fabricated by common casting and hot-forging technology utilizing the reaction between titanium and B4C, graphite. The microstructure, room temperature tensile behavior and fracture characteristics of the composites are presented and discussed. Microstructural analysis of the composites revealed a uniform dispersion of the reinforcements in the Ti-1100 matrix alloy. The ambient-temperature tensile strength of the composites, higher than that of the matrix alloy, increased and ductility decreased with increasing volume fraction of reinforcement. The addition of graphite increased the ambient temperature tensile strength. The intrinsic mechanisms governing the tensile fracture process are discussed.