| 摘要 |
PROBLEM TO BE SOLVED: To provide a bearing for a motor type fuel pump made of a new Zn-P-Ni-Sn-C-Cu based sintered alloy having corrosion resistance to inferior gasoline including sulfur and organic acid and suitably usable even in a miniaturized fuel pump because of its excellent wear resistance and fitness with a mating shaft.SOLUTION: Provided is a sintered bearing having a composition comprising, by mass, 3 to 13% Zn, 0.1 to 0.9% P, 10 to 21% Ni, 3 to 12% Sn and 1 to 8% C, and the balance Cu with inevitable impurities, and having a structure in which an Sn alloy phase including of Sn of 15% or more, by mass, is formed on the grain boundaries of the base made of a solid solution phase of a Zn-Ni-Sn-Cu alloy, also porosity is 8 to 18%, and further, free graphite is distributed inside the pores. |
