CUTTING TOOL AND METHOD OF ITS COATING Russian patent published in 1998 - IPC

FIELD: cutting tools with coatings used in metal machining with formation of chips. SUBSTANCE: cutting tool is coated with one or many heat-resistant layers with some layers distinguishing in controlled microstructure and phase composition with crystal planes preferably growing in direction of surface of coated cutting tool. Said coating includes one or several heat resistant layers of which at least one, is dense fine-grained layer of α-Al₂O₃, preferably, structurized in direction of (012). EFFECT: higher cleanness of surface, wear-resistance and impact elasticity of tool in its use in machining of steel, cast iron and especially in machining of spherulitic iron. 8 cl, 1 dwg