| 摘要 |
<p>PROBLEM TO BE SOLVED: To exhibit excellent chip processing performance in finishing processing by devising a shape of a chip breaker provided on a rake face of a cutting insert.SOLUTION: The cutting insert comprises a corner cutting edge of a nose round part, a straight line cutting edge respectively continuing with both ends of its corner cutting edge, the rake face having a positive rake angle provided along the respective cutting edges and a breaker wall installed on the rake face of the nose round part. The rake angle of the rake face is gradually reduced toward the tail end of the nose round part from a bisection position of the nose round part. A breaker width of the nose round part is also set to 0.5 mm to 0.6 mm, and the breaker wall of a breaker projection is positioned on the corner cutting edge side more than a position of collecting lines orthogonal to respective parts of the corner cutting edge in one place.</p> |
