| 摘要 |
In high efficiency cutting of very hard and hard-to-cut ferrous materials, compared with conventional cBN sintered body tools, the fatigue life of the machined part is improved and a longer lasting tool is provided by controlling the production of the affected layer by machining formed on the machined surface of the workpiece to be cut and by promoting residual of compression stress. The cBN sintered body related to the present invention has not less than 60% and not more than 95% of cBN components in volume, and has a thermal conductivity of 70 W/m·K or more; and the outermost surface thereof is coated with a heat resistant film comprising a compound of at least one element selected from 4a, 5a, 6a group elements and Al, and at least one element selected from C, N and O. |
