| 摘要 |
An insert (1) provided with an insert body having an upper surface (2), a lower surface (3), and side surfaces (4) intersecting the upper surface (2) and the lower surface (3); a cutting edge (6) located at the intersections between the upper surface (2) and side surfaces (4) and provided with a corner cutting edge (61) located at the corner (21) between a first side (22) and a second side (23) which form the upper surface (2) and also with a first cutting edge (62) located at the first side (22); a rake surface (5) located on the upper surface (2) so as to lie along the cutting edge (6); and a projection (7) located on the upper surface (2) at a position inward of the rake surfaces (5). The projection (7) comprises a first surface (71) tilted upward as the first surface extends inward from the cutting edge (6), a second surface (72) located at a position higher than the position of the first surface (71) and inside the first surface (71) relative to the cutting edge (6) and tilted upward as the second surface extends inward from the cutting edge (6), and a third surface (73) located between the first surface (71) and the second surface (72). The intersection (X) between the first surface (71) and the third surface (73) is tilted downward as the intersection is away from the corner cutting edge (61). |
