MICROSTRUCTURE AND ELECTROCHEMICALPERFORMANCE OF ALUMINUM ALLOY SACRIFICIAL ANODES

摘要

The present test program was developed to assess the correlations between the microstructure ofrnAl-Zn-In based alloy sacrificial anode materials and their electrochemical performance. This paperrndiscusses the testing results and how these results can be useful for the development of high efficiencyrnaluminum based alloy sacrificial anodes. The electrochemical performance of Al-Zn-In-Mg-Ti anodes hasrnbeen tested with constant current method in seawater and microstructures were also observed and analyzedrnby metallography and electron probe microanalysis (EPMA). The experiments focused on the influence ofrnmicrostructure on sacrificial anode current efficiency and operating potential performance. Results showedrnthat the current efficiency of anodes increased with the decrease of the amount of the second-phase. Therncurrent efficiency and electrochemical performance of anodes were related to preferential dissolution of thernsecond-phase. The fewer the segregative phases are, the higher the current efficiency is. The correlationsrnbetween the grain size and the electrochemical performance such as current efficiency of Al-Zn-In-Mg-Tirnanodes are not very clear in this study.