| 摘要 |
A cutting insert (20), comprising an upper surface (60), a lower surface (62) and a side surface (64) extending therebetween, the upper and side surfaces (60, 64) intersecting at a cutting edge (66), a cylindrical protrusion (82) having a cylindrical peripheral surface (84) extends downwardly from the lower surface (62) to a bottom surface (86) of the protrusion (82), the cutting insert having an insert axis (B) passing trough the upper and bottom surfaces (60, 86);
the cutting edge (66) comprises at least three cutting edge portions (68) that are separated from each other by corner cutting edges (70) and each cutting edge portion comprises a first convex cutting edge (72) that extends between a second cutting edge (74) and an adjacent corner cutting edge (70). |
