Formation of Refractory Metal Carbide Coatings on Carbon Fibers by a Reaction‐Bonding Process

Abstract

Carbon fiber tows were impregnated by ethanolic solutions of refractory metal chlorides and fired at temperatures up to 2200°C to form metal carbide coatings incorporating carbon from the underlying substrate. Optimum firing sequences were determined for maximum metal carbide conversion. Fired tows were subsequently examined by X‐ray photoelectron and Auger spectroscopy, scanning electron microscopy, and thermogravometric analysis to characterize the coated material. Coatings produced were stable under flowing air at a temperature of 800°C. This process is illustrated for the production of niobium‐based coatings.