Cutting insert and tool for machining a workpiece

Abstract

A cutting insert for a tool for machining a workpiece. The cutting insert comprises a rake face with a chip shaping geometry which is particularly suitable for machining titanium and titanium alloys. The chip shaping geometry is designed in such a way that the chip lifted from the workpiece is deformed comparatively strongly about its longitudinal axis. The chip shaping geometry is arranged at least in a rear area of the rake face, which is laterally bounded by a first concavely curved portion and a second concavely curved portion of the minor cutting edges of the cutting insert. The chip shaping geometry projects upwardly beyond a cutting plane in which the main cutting edge of the cutting insert and two rectilinear portions of the two minor cutting edges are arranged and comprises at least two elevations so that the rake face in the rear area in a further cross-section parallel to the main cutting edge comprises two high points and an intermediate second low point which has an equal third distance from the first concavely curved portion and the second concavely curved portion. A rake angle along the main cutting edge varies such that the rake angle γ1 at a center of the main cutting edge, which has an equal second distance from a first end and a second end of the main cutting edge, is greater than the rake angle in the area of the first and/or second ends.