PORE-FREE SURFACE COATED CERMET CUTTING THROW-AWAY TIP HAVING HARD COATING LAYER EXHIBITING CHIPPING RESISTANCE IN HIGH SPEED CUTTING

摘要

PROBLEM TO BE SOLVED: To provide a pore-free coated cutting tip exhibiting chipping resistance in high speed cutting.;SOLUTION: In this pore-free coated cutting tip fitted to the tool body by clamping and fastening using a clamp piece, a Ti compound layer as a bottom layer and a two-phase mixed oxide layer (Al₂O₃-ZrO₂ layer) of aluminum oxide and zirconium oxide as a top layer are formed on the surface of a tip base by vapor deposition. On the whole surface of the top layer, an abrasive material layer including: a titanium oxide layer satisfying a composition formula: TiO_X wherein X is 1.2 to 1.7 by atomic ratio as a lower layer; and a titanium nitrided oxide layer satisfying a composition formula: TiN_1-Y(O)_Y (wherein (O) indicates diffused oxygen from the titanium oxide layer and Y is 0.01 to 0.4 by atomic ratio) as an upper layer is formed by vapor deposition. In this state, by a wet blast, polishing liquid where Al₂O₃ fine grains are mixed is injected, thereby polishing the surface of the two-phase mixed oxide layer (Al₂O₃-ZrO₂ layer) with the abrasive material layer of the clamp piece abut surface part left undone so that the surface roughness is Ra:0.2 μm or less.;COPYRIGHT: (C)2007,JPO&INPIT