| abstract |
In the sintered alloy for valve guides, the overall composition is, by mass ratio, C: 1.3 to 3%, Cu: 1 to 4%, and the balance is composed of Fe and unavoidable impurities, and has a base structure except pores and pores. The matrix structure is composed of a mixed structure of a pearlite phase, a ferrite phase, an iron carbide phase, and a copper phase, and represents a metal structure in which graphite is dispersed in a part of the pores, and when the cross-sectional metal structure is observed, By area ratio, an iron carbide phase is 3 to 25%, and the said copper phase shall be 0.5 to 3.5%. |