High-Temperature Oxidation Behaviour of a TiAl-Based Alloy Subjected to Aluminium Hot-Dipping

Abstract In this research the oxidation resistance at high temperature of a TiAl-based alloy has been improved by hot-dipping in molten aluminium and performing an interdiffusion process. After selecting best process parameters, compact TiAl 3 coating characterized almost constant thickness was formed on surface. Isothermal tests, carried out 900, 950 1000 °C, showed that coated is able to form continuous thin alumina layer very protective. Microstructural investigations highlighted that, above 900 long residence times determine diffusion through Cr favours migration toward outer surface Al thus formation self-healing layer. Graphical