Effect of surface modification on the stability of oxide scales formed on TiAl intermetallic alloys at high temperature

TiAl intermetallic alloys have many interesting potential application in the automitive and aerospace industry due to their low density and good mechanical properties. Unfortunately they have a low oxidation resistance at temperature higher than 700 °C and the improvement of their oxidation behavior is still an open issue. In this work the surface of a TiAlCrNB alloy has been modified by means of their anodic coating or cerium converison coating. Afterwards the stability of the oxide scale formed at 900 °C has been studied by analyzing crack formation and porpagatin, which is the phenomenon that con produce scale spallation during the alloy cooling.