| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a silicon nitride sintered compact cutting tool and a coated silicon nitride sintered compact cutting tool of a long service life compared with a conventional one in consideration of shifting to high speed cutting with a rise of demand for high efficiency and labor saving in a cutting process in recent years. <P>SOLUTION: The silicon nitride sintered compact cutting tool and the coated silicon nitride sintered compact cutting tool with its surface coated with a coat consists of Y<SB>2</SB>O<SB>3</SB>of 1.2-1.8 wt.%, Al<SB>2</SB>O<SB>3</SB>of 0.3-0.8 wt.% and the rest Si<SB>3</SB>N<SB>4</SB>, wherein a friction coefficient with cast iron is 0.6 or less, and heat conductivity is 40 W/mK or more. The cutting tool realizes a long service life in high speed cutting of cast iron, compared with a conventional silicon nitride sintered compact cutting tool. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
