Oxidation behavior of fully dense TiAl-based composites with a controlled laminated microstructure

Abstract

Abstract A novel laminated TiAl matrix composite (LMC) consisting of alternating equiaxed grain layers (EGLs) and fully lamellar grain layers (FGLs) has been fabricated successfully by hot pressing of alternating Ti/Al–6Si foils and subsequent multi-step reaction annealing. The oxidation behavior of the LMC at 800\xa0°C was studied. The results show that the oxide scale is formed with typical multilayer structure after oxidized at 800\xa0°C for 100\xa0h. The oxidation behavior is different between EGLs and FGLs while the thickness of oxide scale is almost identical, suggesting an isotropy oxidation resistance of the LMC. Si addition effectively enhances the oxidation resistance of the LMC.