Effect of Al Molten Salt Electrodeposition Treatment on High Temperature Oxidation of TiAl Intermetallic Compound

Abstract

An Al deposit layer on TiAl substrate was formed by electrodepositing Al and alloying it with TiAl in molten salt. Electrolysis of Al was conducted using a potentiostatic polarization method at constant potentials in an equimolar NaCl-KCl melt containing 3.5mol% AlF₃ at 1023K. The mass of electrodeposited material increased with decreasing in polarization potential. Deposits formed at -1.3- -1.6V (vs. Ag/Ag⁺ (0.1)) built up a homogeneous layer. These deposits consisted of TiAl₃. TiAl covered by the electrodeposit layer was more resistant than bare TiAl to high temperature oxidation.