EFFECT OF HEAT-TREATMENT ON TENSILE PROPERTIES OF ZINC-37.5 MASS-PERCENT-ALUMINUM ALLOY CONTAINING NICKEL OR SILICON

Attention has been focussed in this study to understand the influence of microstructural changes brought about through T6 type heat treatmen t on the tensile strength and elongation of some zinc-37.5 mass%alumin ium based alloys comprising nickel/silicon. Other (test) variables who se effects were studied include strain rate (at room temperature) and test temperature (at a typical strain rate). The study indicates that heat treatment and test conditions (strain rate and test temperature) affect the tensile properties of the zinc-based alloys to varying exte nts. The response of the alloys under different test conditions has be en explained on the basis of specific characteristics of their various microconstituents. It has been observed that factors like microcracki ng tendency and thermal stability greatly control the mechanical prope rties of the samples. The predominance of the parameters over each oth er depends on the test conditions. Accordingly, the alloys exhibit cha nging properties as the condition of testing alters.