Infrared infiltration and properties of SCS-6/Ti alloy composites

Abstract

Liquid infiltration processes are seldom used in the fabrication of titanium matrix composites primarily because of severe interfacial reactions during processing. To minimize fibre-matrix interfacial reactions, a rapid infrared manufacturing (RIM) process has been developed. In this study, SCS-6 fibre reinforced titanium matrix composites were fabricated by the RIM process. Experimental results indicate that composites prepared by the RIM process exhibit small interfacial reaction zones and superior mechanical properties compared to diffusion bonded composites. Interfacial reactions during processing in this composite system have been investigated. Microscopic analyses showed that the carbon-rich coating present on SCS-6 fibres partially dissolved in the alloy during infiltration without forming a continuous reaction product. A physical model has been proposed to explain the dissolution mechanism of the carbon-rich coating. The dissolution rate of the coating at the processing temperature of 1300 °C was calculated to be 1.4×10−6 cm s−1.