Thermal stability of Sic-Scs-6 fiber-reinforced im1834 alloys

One of the major future applications of titanium matrix composites is as a material for airplane turbine components, e.g., in the compressor. Service temperatures of up to 800 C will be involved. This application objective will only be reached when it will be possible to solve two major material problems: first, a matrix with sufficient ductility at room temperature and sufficient strength at service temperatures has to be found; and second, the problem of fiber/matrix reaction at application temperatures has to be solved. In composites with the high ductility IMI834 alloy (Ti-5.8Al-4.0Sn-3.5Zr-0.7Nb-0.5Mo-0.35Si-0.06C in wt. pct) as matrix, the optimal tensile properties can be exploited: the ultimate tensile strength and Young`s modulus values are in accordance with the prediction of the rule of mixtures, and an elongation at fracture of nearly 1.3 pct, typical of SiC fibers, is measured. It was shown that in SiC-SCS-6 fiber-reinforced IMI834 composites, these properties are achieved up to temperatures of 1,000 C. In the present study, results of the thermal stability of the SiC-SCS-6 fiber-reinforced IMI834 alloys are presented.