SINTERED ALLOY-MADE VALVE GUIDE FOR INTERNAL COMBUSTION ENGINE

摘要

PURPOSE: To contribute to improvement of performance of an internal combustion engine by making a valve guide having the good seizure resistance and the abrasion resistance without increasing the consumption of lubricating oil. CONSTITUTION: A valve guide is made of iron-carbon sintered alloy having the density ratio ranging from 80 to 86.5%, most powder grain diameters of alloy matrix are in the range of 74 to 250μm, the air permeability is, 20 to 45×10<-3> darcy, and lubricating oil are impregnated into pores. The pores are narrowed by fixing silicone resin in which silicone resin or solid lubricant grains are dispersed into the pares at least on the front layer part.