Ph.D. Tezi Görüntüleme | |||||||||||||||||||||
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| Summary: In this study, one binary Zn-30Al, five ternary Zn-30Al-(1-5)3Cu and six quaternary Zn-30Al-3Cu-(0.5-5)Si alloys were prepared by permanent mold casting. Tribological properties of these alloys were studied using a block-on-disk machine after determining their microstructural and mechanical properties. The microstructure of binary Zn-30Al alloy is composed of α, β and η phases. The microstructure of the ternary Zn-30Al-(1-5)Cu alloys contained ε phase in addition to the phases present in the binary alloy, and the quaternary Zn-30Al-3Cu-(0,5-5)Si alloys revealed silicon particles in addition to the phases observed in the ternary alloys. The hardness and the tensile strength of the ternary alloys increased, but their ductility decreased with copper content. The tensile strength of quaternary alloys increased with silicon content up to % 1, above which the trend reversed. However, the hardness of the quaternary alloys increased with increasing silicon content. Among the ternary and the quaternary alloys, the highest wear resistance was obtained from Zn-30Al-3Cu and Zn-30Al-3Cu-0.5Si alloys, respectively. The temperature and wear volume of the experimental alloys increased, but their friction coefficient decreased with contact pressure. However, the values of these properties increased with sliding velocity in both lubricated and unlubricated conditions. The wear resistance of Zn-30Al based ternary and quaternary alloys were found to be higher than those of SAE 65 and SAE 660 bronzes.Correlation of the experimental data resulted in the determination of tribological property-Cu/Si content-test parameter relationships for the Zn-30Al-based alloys. In addition, the equations for estimation of the friction coefficient and the wear volume of the Zn-30Al-3Cu and Zn-30Al-3Cu-0.5Si alloys which have the highest wear resistance among the experimental alloys were derived. Key Words: Zn-30Al Based Alloys, Microstructure, Mechanical properties, Friction and wear, Wear volume-test parameter relationship | |||||||||||||||||||||