Interface properties of Ti3SiC2/Al2O3 ceramics: Combined experiments and first-principles calculations

The synthesis, characterization, and first-principles calculations of Ti₃SiC₂/Al₂O₃ ceramics were reported. X-ray diffraction measurements showed that the composite ceramics were highly pure. Scanning electron microscopy and transmission electron microscopy were used to characterize the interface information for Ti₃SiC₂ and Al₂O₃ crystals. Surface energies and interface properties were calculated using the first-principles method. The results suggested that Ti₃SiC₂ with Ti terminations and Al₂O₃ with O terminations are more stable than other terminations crystals. Thus powerful attraction between the coordinatively unsaturated Ti and O atoms on the Ti₃SiC₂∥Al₂O₃ interface would result in higher work of adhesion (Wad) and shorter boundary distance, demonstrating the intercrystalline strengthening of Ti₃SiC₂/Al₂O₃ composite ceramics.