| 摘要 |
PROBLEM TO BE SOLVED: To provide: a composite material of a WC-based cemented carbide member having high transverse rupture strength and a steel member; and a shaft-like object cutting tool such as an end mill and a drill which has high cutting performance and is composed of the composite material.SOLUTION: The composite material of the WC-based cemented carbide member and the steel member is provided in which the WC-based cemented carbide member and the steel member are joined to each other via an intermediate member material mainly composed of Ni. In the composite material, (a) in a flat end surface opposed to the intermediate member, of the WC-based cemented carbide member, a plurality of recessed parts occupying 1-5 area % of the whole area of the flat end surface and having a width and a depth respectively of 0.4-1% and 0.1-0.5% of an outer diameter of the WC-based cemented carbide member, are partially formed in a recessed condition, and (c) in the intermediate member filled into the recessed part, a Co-enriched area having a Co content higher than the average Co content of the intermediate member is formed and WC particles are dispersedly distributed. |
