Coated cutting insert and method of making it

摘要

PCT No. PCT/SE96/01579 Sec. 371 Date Sep. 1, 1998 Sec. 102(e) Date Sep. 1, 1998 PCT Filed Nov. 29, 1996 PCT Pub. No. WO97/20083 PCT Pub. Date Jun. 5, 1997A coated turning insert particularly useful for dry and wet machining in low and medium alloyed steels, stainless steels, with or without raw surface zones under severe conditions such as vibrations, long overhang and recutting of chips. The insert is characterized by a WC-Co cemented carbide with a low content of cubic carbides and a rather low W-alloyed binder phase and a coating including an innermost layer of TiCxNyOz with columnar grains and a top layer of TiN and an intermediate layer of kappa -Al2O3. The layers are deposited by using CVD-methods.