Drill for composite material as well as machining method using same and machining apparatus using same

Abstract

An object is to provide a drill for a composite material which can realize high-quality boring hardly causing burrs or delamination in boring of a member to be machined containing a fiber reinforced composite material at least partially. A drill 1 for a composite material has a tip portion on which a tip cutting edge 5 is formed, a tapered portion 4 formed so as to be connected to the rear end side of the tip portion and formed so as to have a tapered shape with a diameter difference between an outer diameter on the tip side and a diameter on the rear end side larger than the diameter on the tip side, and a straight portion 3 formed so as to be connected to the rear end side of the tapered portion 4 and formed entirely so as to have the same diameter such that a finishing machining diameter larger than the outer diameter on the rear end side of the tapered portion 4 can be formed, and a helically twisted outer peripheral cutting edge 7 is formed on an outer periphery of the tapered portion 4 and set so that a boring diameter becomes continuously larger.

Dependencies are inferred from the claim text.