Intermetallic materials with excellent resistance to high temperature oxidation have been considered as potential replacements for superalloys used as aerospace materials. Titanium aluminides are especially attractive for this role (1-7). However, further commercialization of titanium aluminides requires the development of non-conventional machining, such as electrochemical machnining (ECM) (8). As a first attempt in the development of the ECM process, the corrosion behavior of arc-melted #gamma# TiAl and #alpha# 2 Ti_3Al was investigated along with pure titanium and aluminum in deaerated and non-deaerated solutions of sulfuric acid, sodium sulfate, and sodium hydroxide. Two types of electro-chemical experiments were carried out, namely: potentiodynamic and potentiostatic. In the Na_2SO_4 solution, the highest current was found for Al and the lowest for TiAl. The shape of the plarization curves indicates that the intermetallics show similar behavior to that of Ti.
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