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

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 degrees C was studied. The results show that the oxide scale is formed with typical multilayer structure after oxidized at 800 degrees C for 100 h. 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. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

A novel laminated TiAl matrix composite with alternating equiaxed grain layers and fully lamellar grain layers was successfully fabricated using hot pressing and multi-step reaction annealing. The oxidation behavior of the composite at 800 degrees C was studied, showing a typical multilayer oxide scale structure. Although there were differences in oxidation behavior between different grain layers, the thickness of the oxide scale was almost identical, indicating isotropic oxidation resistance. The addition of Si effectively enhanced the oxidation resistance of the composite.