Relationships between secondary dendrite arm spacing and mechanical properties of Zn-40Al-Cu alloys

Three ternary monotectoid-based Zn-40Al-(1, 2, 3%) Cu alloys were produced by permanent mould casting at different pouring and mould temperatures. The average cooling rate for each alloy was determined. Structure of the alloys was examined using optical and electron microscopes and their hardness, tensile strength, percentage elongation and impact energy were measured. As a result of these investigations the relationships between structure and mechanical properties of the alloys were determined.It was observed that the secondary dendrite arm spacing of the alloys decreased with increasing cooling rate and their hardness, tensile strength, percentage elongation and impact energy increased. Correlation of experimental results showed that the hardness, tensile strength, percentage elongation and impact energy of the alloys could be related to their secondary dendrite arm spacing using straight line equations.