Preparation and properties of silicon carbide-coated boron filaments☆

Abstract Silicon carbide-coated boron filaments have been produced both in a continuous and in a two-step process. The silicon carbide coating inhibits the oxidation of boron and also impedes the diffusion of boron into an aluminum or titanium matrix at elevated temperatures. As a consequence, these composite fibers retain their room temperature strength after being exposed to 600°C for 500 hours in aluminum or titanium. In addition, the relative resistance to attack of the filaments allows certain high temperature reinforced metal composite fabrication techniques to be employed which are not possible with uncoated boron filaments.