| 摘要 |
PROBLEM TO BE SOLVED: To provide a throw-away tip made of cermet having a fine hard phase structure and further having high bending fracture strength, and in which characteristic variation between samples is reduced. SOLUTION: Disclosed is a throw-away tip made of cermet composed of: a bonding phase essentially consisting of Co and/or Ni by 1 to 30 mass%; and a hard phase composed of a compound metal carbonitride of Ti and one or more kinds selected from the group 4a, 5a and 6a metals in the periodic table other than Ti by 70 to 99 mass%, and in which the average particle diameter of the hard phase is≤1.5μm, and further,≥50% of a fracture source observed at the fracture surfaces after the measurement of the bending fracture strength of bending fracture test pieces cut from the cermet is composed of voids in which a part or the whole of the surface is covered with an elution layer of Co and/or Ni. COPYRIGHT: (C)2009,JPO&INPIT |
