摘要 |
A cutting insert 1 includes a land 9 and a breaker flute 10 on a rake face, the land 9 providing a cutting edge 4 by intersecting a flank face 3. The breaker flute 10 includes breakers 11. A width T of a portion of the land 9 that extends along a portion of the cutting edge that is at a round corner portion is 0.05 mm < T < 0.15 mm. A plurality of crest portions 12 each extending over the entirety of the portion of the cutting edge that is at the round corner portion are provided on a sloping surface of the breaker flute 10 that is on a land side. The crest portions 12 are arranged side by side in a depth direction of the breaker flute 10. A rake angle ¸ of at least one of inclined surfaces that form each of the crest portions is expressed as ¸ > 20°. |