Preparation Of Continuous SiC Fiber Reinforced Titanium 600 Matrix Composites

The continuous silicon carbide fiber (SiC) reinforced titanium matrix composites (TMC) make full use of constitutive properties such as higher strength and toughness of silicon carbide fiber, plasticity and mold ability of titanium matrix. These all make it keep better fatigue and creep resistance at elevated temperature up to 600～800℃. TMC has attracted considerable interest as materials for components in elevated temperature aerospace and gas turbine applications because of higher specific tenacity and modulus, outstanding fatigue and creep properties, wonderful elevated temperature property and erosion resistance.The way of matrix-coated fiber was used to manufacture the composite of Ti600 reinforced with the domestic SiC fiber. For comparison, the SiC/Ti-6Al-4V was also prepared. Under the conditions of 40w/lh for cleaning the fiber and 800W/2.0Pa/ 2.0h+800W/3.0Pa/8.0h for sputtering the matrix alloy with faster deposit rate, the nano grained Ti600 and Ti-6Al-4V alloys were deposited onto the SiC fiber with exellent bonding between fiber and coating, homogeneous thickness and chamical composition.The interfacial reaction of the composites was investigated by means of scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectrometer (EDS) and the effect on the tensile property was discussed. The interfacial reaction products of SiC/Ti600, SiC/Ti-6Al-4V and SiC/C/Ti-6Al-4V were compared. The interfacial reaction products of SiC/Ti600 are basically the same as those of SiC/Ti-6Al-4V, mainly TiC, Ti₅Si₃ and Ti₃SiC₂. But only TiC was found as interfacial reaction product of the SiC/C/Ti-6Al-4V composite because of the C coating on the outmost surface of the SiC fiber. The kinetic values of K₀ and Q^k for the growth of the interfacial reaction zone in the SiC/Ti600, SiC/Ti-6Al-4V and SiC/C/Ti-6Al-4V composites were obtained and compared. It is shown that the interface of SiC/Ti600 is more stable than that of the other two kinds of composites. However, the longitudinal tensile strength of SiC/Ti600 is very poor due to the poor...