| 摘要 |
PURPOSE:To prepare a high toughness coating tool having excellent wear resistance, by forming a non bonded part in a boundary when coating the surface of a super hardness alloy with a layer of carbide, nitride or oxide of a specific metal. CONSTITUTION:High hardness coating comprising carbide, nitride or oxide of a metal of 4a, 5a and 6a group metals, Al, Si or B is formed on the surface of a tool made of a super hardness alloy having a powdered hard metallic oxide or metallic nitride sintered with an iron group metal as a binding material and thus a coating tool having excellent wear resistance and deposition resistance is obtained. In this process, on a boundary between a sintered super hardness alloy substrate and a high hardness coating layer, carbon which is round plate-shaped and 20mum or less long in the maximum length or is round cube-shaped and 20mum or less long in the maximum length of a section and which has its exposed area accounting for 0.1-20% of the boundary is deposited, thereby providing the non bonded part of the boundary. The super hardness tool has improved toughness and chipping of its edge hardly occurs. |
