Cutting insert and rotary cutting tool

Abstract

An object is to provide a cutting insert having improved durability. For solving the problem, the cutting insert of the present disclosure includes a major cutting edge 11a and a wiper insert 11b each formed of CBN. A chamfer 1124 extending to the major cutting edge 11a and including a smooth surface formed at least near the major cutting edge 11a is formed on a rake surface 1121 of the wiper insert 11b. The smooth chamfer eliminates a portion on which stress concentrates, and prevents occurrence of chipping or the like, thereby improving durability. A portion of the chamfer on the major cutting edge side preferably has a rounded convex shape. Since the portion on the major cutting edge side is formed in a rounded convex shape, an effect similar to that obtained when a chamfer is formed without formation of a ridgeline portion is obtained.

Dependencies are inferred from the claim text.