A FIBER COATING PROCESS FOR ADVANCED METAL-MATRIX COMPOSITES

A fibre coating process has been used to produce continuously reinforced advanced metal-matrix composites with up to 8% volume fraction of SiC fibre. Matrix materials were an α/β titanium alloy (Ti-Al-V), a dispersion-strengthened titanium alloy (Ti-Al-V-Y), a rapid solidification processed aluminium alloy (Al-4.3Cr-0.3Fe), and intermetallic compounds Ti3Al and TiAl. Thick metal coatings are shown to adhere well to the fibres, no evidence is found for chemical reaction between the coating and the fibre during the coating process, and the coated fibres can be handled and bent without damage. Tensile test data for Ti-Al-V alloy reinforced with 21% SiC fibre show a modulus near to a theoretical prediction, but tensile strength significantly below prediction. Loss of strength is attributed to the formation of a brittle reaction product during hot consolidation. The advantages and potential of the coated-fibre route for MMC production are discussed. © 1990 Chapman and Hall Ltd.