| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cutting tool superior in fusion resistance and wear resistance. <P>SOLUTION: A cutting insert 1 is a negative type and has a coating layer formed on a surface of a cemented carbide base. The coating layer has a total thickness of 9 to 25 μm and contains a TiCN layer, an Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>layer, and a Ti(C<SB POS="POST">x</SB>N<SB POS="POST">y</SB>O<SB POS="POST">z</SB>)<SB POS="POST">a</SB>layer as a surface layer (wherein x+y+z=1, 0≤x≤0.6, 0≤y≤0.6, 0.2≤z≤0.8, 1.0≤a≤1.7) from a base side. A plurality of cutting edges are formed in an intersecting edge line part of a top surface 2 and a side surface 4, each cutting edge 5 containing a main cutting edge 51, a sub-cutting edge 53, and a flat cutting edge 52 as one set. A land part 6 is formed at a position adjacent to the cutting edge 5 of a rake face (top surface) 2. A sub-cutting edge land part 63 corresponding to the sub-cutting edge 53 is sloped toward a central part of the top surface 2 as if approaching a bottom surface. <P>COPYRIGHT: (C)2012,JPO&INPIT |
