Influence of Cooling Rate and Copper Content on the Microstructure of Zn–27%Al Alloy under End-chill Casting

مهندسی متالورژی و مواد

Article 3, Volume 28, Issue 2 - Serial Number 16, August 2017, Pages 27-36   

Document Type: Original Articles

DOI: 10.22067/ma.v28i2.35765

Authors

Rahim Arabi Jeshvaghani^* ; Hamid Pirnajmoddin; Hassan Ghahvechian; Hamid Reza Shahverdi

Tarbiat Modares University

Abstract

In this research, the effect of cooling rate and copper content on the microstructure of Zn–27%Al alloy was investigated using chilled casting in a sand mould. Microstructural examination showed that with decreasing cooling rate, dendrite arm spacing and the percentage of interdendritic phases increased. Moreover, addition of copper up to 1 wt. % did not lead to significant change in microstructure, while addition of 2, and 4 wt% copper led to the formation of -CuZn4 phase in the interdendritic regions. In addition, with decreasing cooling rate, the morphology of - precipitates varied from semi-plate-like to spherical.

Keywords

End-Chill Casting; ZA27 Alloy; Microstructure; Cooling rate

Supplementary Files

3-najmodin_AK_EDITS.pdf

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