| 摘要 |
In a valve seat made of an iron-based, composite sintered alloy having hard particles and a solid lubricant dispersed therein to have high wear resistance and good machinability, which is usable in high-power fuel direct injection engines with improved fuel efficiency and low emission, relatively coarse solid lubricant particles in such an amount as not to drastically reduce the strength of a sintered body are dispersed to provide self-lubrication, and as fine solid lubricant particles as not hindering the bonding of matrix particles are dispersed to improve machinability. |
