Characteristics and cutting perfomance of the CVD coatings on the TiCN-based cermets in turning hardened AISI H13 steel

CVD coatings were deposited on the cermets and cemented carbides tools. Uncoated cermets, coated cermets and cemented carbides tools were used for hardened AISI H13 steel machining. Face-centered cubic structure of the cermets attribute to the direct growth of the TiN coatings. TiN and TiCN shows (2 0 0) preferred orientation on the cermets. The hexagonal closepacked structure of the cemented carbides make the TiN coatings nucleate first and then grow. TiN and TiCN shows (1 1 1) preferred orientation on the cemented carbides. When the cutting speed reaches and exceeds 700r/min, the coated cermets have the longest life. The excellent diffusion and adhension wear resistance at elevated temperature of the coated cermets result a better surface quality of workpiece.