Patent attributes
A cutting insert having an insert body formed in a shaft-shape, wherein a cutting edge portion having a square rake face is formed on an end portion of the insert body, and wherein the rake face includes: a pair of side cutting edges extending in a longitudinal direction of the insert body; a front cutting edge extending in a transverse direction perpendicular to the longitudinal direction between each front end of the side cutting edges; a pair of protruded streaks extending toward each of corner portions at which each of the side cutting edges intersect the front cutting edge, and a projection which protrudes and is separated from the protruded streaks between front ends of the protruded streaks in the vicinity of the corner portion and the corner portion.