Microstructure and Property Characterization of a Modified Zinc-Base Alloy and Comparison with Bearing Alloys

The microstructure and physical, mechanical, and tribological properties of a modified zinc-base alloy have been characterized. In order to assess its utility as a bearing alloy, its properties have also been compared with those of a similarly processed conventional zinc-base alloy and a leaded-tin bronze (conformingto ZA27 and SAE 660 specifications, respectively) used for bearing applications.The modified zinc-base alloy shows promise in terms of better elevated-temperature strength and wearresponse at higher sliding speeds relative to the conventional zinc-base alloy. Interestingly, the wear behavior(especially the seizure pressure) of the modified alloy was also comparable to that of the bronzespecimens at the maximum sliding speed, and was superior at the minimum sliding speed. The modifiedalloy also attained lower density and better hardness. Alloy behavior has been linked to the nature andtype of the alloy microconstituents. © 1997, ASM International.