| 摘要 |
A cutting insert (1) includes an end cutting edge (5a) located along an intersection of an upper surface (2) and a front clearance surface (4a), and a pair of side cutting edges (5b) respectively located along intersections of the upper surface (2) and a pair of side clearance surfaces (4b). The upper surface (2) includes an end rake surface (21a) that is continuous with the end cutting edge (5a) and is inclined downward as departing from the end cutting edge (5a), a pair of major protrusions (22a) that are located apart from the end cutting edge (5a) and are less apart from each other as departing from the end cutting edge (5a) in a top view, and a pair of minor protrusions (22d) that are respectively located close to their adjacent side clearance surface (4b) of the pair of side clearance surface (4b) with respect to the pair of major protrusions (22a) in the top view. The pair of minor protrusions (22d) are located further apart from the end cutting edge (5a) than an end portion of each of the pair of major protrusions (22a) which is close to the end cutting edge (5a). A top portion of each of the pair of minor protrusions (22d) is lower than a top portion of each of the major protrusions (22a). |
