Though Mg alloys are the outstanding candidates for the use in automotive, aerospace and electronic industries because of their low density and excellent strength to weight ratio, they have a great disadvantage in corrosion resistance. In this study, their corrosion behavior has been investigated by the polarization test and electrochemical impedance spectroscopy test for their practical use. AZ series Mg alloy samples produced by conventional ingot metallurgy showed a little slight decrease Ecorr with an increase of Al content, while they indicated a remarkable decrement of Icorr with increasing amount of Al content.
