Recently automotive fuel pumps installed in the fuel tank are still striving to increase the demands for high efficiency and high quality assurance. And as automotive supply continues to become increasingly global, the pumps have been used under various inferior gasoline containing higher sulfur concentrations in developing markets as compared with in general industrialized markets. Traditionally bronze alloy of Cu-Sn-C system is mainly used for the typical bearing of fuel pump applications. However it is very difficult to improve remarkably on the tribological performances of the demands for higher efficiency and so on. And what is more, the relatively high sulfur and sulfide contents gasoline is easy to cause sulfuration corrosion.
In order to obtain excellent tribological performances and superior resistive to sulfuration, various copper based alloy of sintered bearings are investigated by powder metallurgy method. As a result, nickel silver alloy of Cu-Ni-Zn-C system shows both superior resistive to sulfuration and excellent tribological performance under the relatively high sulfur contents gasoline lubrication.