TITLE:
Effects of Tin on Aluminum–Zinc–Magnesium Alloy as Sacrificial Anode in Seawater
AUTHORS:
L.E. Umoru, O.O. Ige
KEYWORDS:
Corrosion, sacrificial anode, aluminium alloy, tin, efficiency and microstructures
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.7 No.2,
June
20,
2008
ABSTRACT: This work has investigated the effect of tin composition on Al-Zn-Mg alloy as sacrificial anode in seawater. Corrosion experiments were mounted to determine the optimal effect of tin on the efficiencies of the aluminium alloy anodes. The corroded and unexposed sample surfaces were subject to microstructural characterization using optical microscopy technique. Al-Zn-Mg alloy doped with 0%, 0.01%, 0.05% and 0.1% by weights of tin were prepared to determine the effect of tin on anode efficiency in the environment. The different microstructures of the Al-Zn-Mg-Sn alloy evolved were correlated with the anode efficiencies. The results obtained showed that the anode efficiency of Al-Zn-Mg-Sn alloy increased with tin concentration. The Al-Zn-Mg-0.1Sn gave the best anode efficiency. The microstructures of the Al-Zn-Mg-Sn alloys revealed increased distribution of tin globules and a breakdown of passive alumina film network on the anodes surfaces and thus improving the anode efficiencies