Patents

In order to improve the oxidation resistance of carbon fiber, a boron nitride coating was developed by a non-hazardous and cost-effective dip coat technique. Dip coating was carried out in saturated boric acid solution followed by nitridation to produce BN coating. Before dip coating, the carbon fibers were chemically activated. Due to interaction of activating chemical agents during the activation treatment, the surface properties, e.g. surface area, surface microstructure of the carbon fibers were significantly varied. These improvements of surface properties subsequently reduce the boron nitride coating formation temperature.