| 摘要 |
[Object] To provide a cutting insert capable of performing good chip control. [Solution] A cutting insert (1) includes: a prism-shaped insert body (2); a rake face (3) on an upper surface of an end portion of the insert body (2) in a longitudinal direction; a cutting edge (4) on a ridge line between the rake face (3) and an end surface of the insert body (2); side cutting edges (5) on ridge lines between the rake face (3) and side surfaces of the insert body (2), being respectively connected to both end portions of the front cutting edge (4); and a breaker convex portion (6) on the rake face (3). The breaker convex portion (6) includes two breaker island portions (10) which extend toward the side cutting edge (5) sides as extending closer to the front cutting edge (4) side. The breaker island portions (10) each include from the front cutting edge (4) side a first raised portion (13), a descending portion (14) which gradually becomes lower from a top portion of the first raised portion (13), and a second raised portion (15) which gradually becomes higher, from the descending portion (14), than the top portion of the first raised portion (13). |
