Drill made of cermet

Abstract

Abstract PURPOSE:To provide high accuracy in a finished surface for a long time by providing the composition containing Ti carbide or the like as hard dispersed phase and Co or the like as combined phase and having specifiled Rockwell hardness while having a specified average size of grain of the hard dispersed phase. CONSTITUTION:The composition is provided which contains one or at least two kinds of TiC, NiN and TiCN as main hard dispersed phase forming components and further one or two kinds of Co and Ni as main combined phase forming component. Also, the hardness of cermet is 88-91.5 of Rockwell hardness A scale (HRA). The desired antiwear property cannot be ensured by 88 or less and the breaking strength is degraded by 91.5 or more. Next, the average size of grain of hard dispersed phase of cermet is 0.5-1.5mum and 0.5mum or less of grain size is difficult to manufacture by the present technique and 1.5mum or more degrades the heat and shock resisting property to generate cracks easily so that the cracks result in chipping to promote wear.

Inventors

• 👤 Kazuyoshi Yoshioka
• 👤 吉岡　一价
• 👤 Shinichi Sekiya
• 👤 関谷　真一

Bibliographic Details