Cubic boron nitride (c-BN) is one of the most perspective hard coating materials for its unique chemical and physical properties such as high hardness next to diamond,high chemical and thermal stability,and not reacting with ferrous metals.The major problem in the depositing c-BN on high speed steels is the poor adhesion.As the amorphous boron nitride (a-BN) or hexagonal boron nitride (h-BN) exists always between the c-BN film and high speed steels substrate.