SINTERED HARD ALLOY BASE MATERIAL FOR SURFACE-COATED GEAR CUTTING TOOL AND SURFACE-COATED GEAR CUTTING TOOL

摘要

This cemented carbide material for a surface coated gear cutting tool is employed in a substrate for a surface coated gear cutting tool which is obtained by forming a hard coated layer on a surface of the substrate, the cemented carbide material for a surface coated gear cutting tool includes a WC-βt-Co based cemented carbide, wherein a content of Co forming a binder phase of the cemented carbide material is in a range of 12 to 17 wt%, and among components of a βt solid solution forming a hard phase of the cemented carbide material, 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%.