FORMATION OF BORON-NITRIDE AND BORON-CARBIDE COMPOSITE BY NITROGEN IMPLANTATION AT ELEVATED-TEMPERATURE

Boron carbide (B4C) is a wear resistant material with hardness slightl y less than that of diamond. It has an excellent strength to weight ra tio and relatively high toughness under controlled processing. These e ssential mechanical properties make B4C an ideal candidate for cutting tool and bearing applications. We will demonstrate that hexagonal bor on nitride (h-BN), a good solid lubricant, can be formed on B4C surfac es through high temperature (850-degrees-C) nitrogen ion implantation. The formation of composite B4C and h-BN on the B4C surface can potent ially reduce surface friction coefficients, making the material more a ttractive for tribological applications.