Sintered hard alloy base amterial for surface-coated gear cutting tool and surface coated gear cutting tool

A cemented carbide material for a surface coated gear cutting tool which is employed in a substrate for a surface coated gear cutting tool obtained by forming a hard coated layer on a surface of said substrate,

• said cemented carbide material for a surface coated gear cutting tool comprising a WC-βt-Co based cemented carbide,
• wherein a content of Co forming a binder phase of said cemented carbide material for a surface coated gear cutting tool is in a range of 12 to 17 wt %, and
• among components of a βt solid solution forming a hard phase of said cemented carbide material for a surface coated gear cutting tool, a content of components excluding WC is in a range of 15 to 20 wt %, and a total content of Ta carbonitride and Nb caronitride is in a range of 5 to 8 wt %.