Abstract
Various barrier coatings were deposited on PAN-based high strength type carbon fibers from vapor phase. The coatings were carbon layer (C) or various double layers consisting of a carbon under-layer and a ceramic over layer (denoted by C/TiC, C/TiN, C/SiC). After Ti-B m, ixture was coated on the fibers, molten aluminum alloy was infiltrated to prepare CFRAI wire. These wires were heated at 500°C for 3 days in a vacuum. Tensile strength of the wire, tensile strength of the filament in the wire, filament pull-out length at tensile fracture surface and the amount of formed aluminum carbide were measured. Among these coatings, C and C/TiC had low effect as a reaction barrier between fiber and aluminum, while the interfacial bonding strength between the coated carbon fiber and aluminum increased by the heat treatment. Though C/SiC and C/TiN had high effect to reduce the reaction, the interfacial bonding strength decreased by the heat treatment. Totally judging, C/SiC was the best among these barrier coatings.
