Sintered bearing for motor type fuel pump with outstanding corrosion resistance wear resistance and conformability

摘要

pThe purpose of the present invention is to provide a bearing for a motor type fuel pump that has corrosion resistance against poor quality gasoline that includes sulfur or organic acids that because of resistance to wear and outstanding conformability with a coupled shaft can be used favorably even in compact fuel pumps and that is made of a novel Zn P Ni Sn C Cu based sintered alloy. The bearing is characterized by having a structure in which contained are by weight 3 13% Zn 0.1 0.9% P 10 21% Ni 3 12% Sn and 1 8% C with the remainder consisting of Cu and unavoidable impurities in which an Sn alloy phase that comprises at least 15% Sn by weight is formed on grain boundaries of a base comprising a solid solution phase of a Zn Ni Sn Cu alloy and in which the porosity is 8 18% and free graphite is distributed in the pores./p