High-temperature tensile properties of in situ-synthesized titanium matrix composites with strong dependence on strain rates

Abstract

High-temperature titanium matrix composites reinforced with hybrid reinforcements are synthesized by common casting and hot working technologies. Tensile properties are tested at different temperatures and strain rates. Ultimate strengths of the composites are significantly enhanced under all conditions and decrease when the strain rate is lower. Equicohesive temperature of the matrix is around 873 K at the strain rate 10−3s−1 and well below 873 K at 10−5s−1. At higher temperature or lower strain rate, interfacial debonding is more drastic and reduces the strengths of composites. The materials are embrittled under creep-rupture conditions. Strict reinforcement morphology is required for more complex service conditions at high temperatures in metal matrix composites.