COMPOSITE MATERIAL OF CEMENTED CARBIDE ALLOY MEMBER AND STEEL MEMBER, AND ROTARY SHAFT-LIKE CUTTING TOOL COMPOSED OF THE SAME MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a composite material of a cemented carbide alloy member and a steel member having high deflective strength, and a shaft-like cutting tool such as an end mill or a drill composed of the composite material and having high cutting performance.SOLUTION: In a composite material of a cemented carbide alloy member and a steel member in which the cemented carbide alloy member and the steel member are joined via an intermediate member, (a) the intermediate member is composed of a Ni containing member, (b) surface roughness of an end face of the steel member facing the intermediate member is formed by being adjusted to Rz5-18 in advance, and (c) when the composite material is observed in a vertical cross section including a shaft center of the composite material, a wedge-like structure in which the intermediate member component is bitten into the steel member is formed in at least one part in a joining boundary region between the intermediate member and the end face of the steel member. In a rotary shaft-like cutting tool, cutting edging machining is performed for the cemented carbide member.