Hard and Highly Adhesive AlMgB Coatings RF Sputtered on Tungsten Carbide and High-Speed Steel.

We report a new industrial application of aluminum magnesium boride AlMgB (BAM) coatings to enhance the hardness of tungsten carbide ceramic (WC-Co) and high-speed steel tools. BAM films were deposited by RF magnetron sputtering of a single dense stoichiometric ceramic target onto commercial WC-Co turning inserts and R6M5 steel drill bits. High target sputtering power and sufficiently short target-to-substrate distance were found to be critical processing conditions.