Abstract:High quality Zn-base powder with low oxygen content, fine particle size and fine microstructure can be obtained by gas atomization using nitrogen. Cast and sintered Zn-27%Al alloys (ZMJ) were prepared. Tribological behaviors of the cast and sintered alloys under lubricated and nonlubricated conditions were studied and compared. Worn surfaces and microstructures of these alloys were examined. Results indicate that although the strength of the sintered alloy is considerably less than that of the cast alloy, the sintered alloy has a better wear resistance. The fine microstructure obtained by rap id solidification is beneficial to the wear-resisting property. The wear volume of sintered ZMJ is only 36% and 59% of the wear volume that found in cast ZMJ under non-lubricated and lubricated conditions, respectively. For lubricated wear test, abrasive wear is the major wear mechanism and for non-lubricated wear test, oxidation wear and adhesive wear are the major wear mechanisms.

Key words: powder metallurgy; Zn-27%Al; tribological behavior; intermetallic phases; undulated surface