Different evolution behaviors of Ti3AlC2 and Ti2AlN structures and surfaces with Ti, Al, C, N vacancy: The core of microscopic configuration design

• Published in: Materials today communications 2025-01, Vol.42, Article 111171
• Main Authors: Zhuang, Weici, Huang, Zhenying, Li, Xue, Wu, Youbo, Sun, Qianwen, Liao, Ziling, Zhu, Ziqiang, Han, Haozheng, Hu, Wenqiang, Pei, Dingfeng, Zhou, Yang
• Format: Article
• Language: English
• Subjects: Al3Ti; Microscopic configuration design; Ti2AlN; Ti3AlC2
• ISSN: 2352-4928; 2352-4928
• DOI: 10.1016/j.mtcomm.2024.111171

To streamline the microscopic configuration design of the composites using Ti2AlN and Ti3AlC2 as precursors, comprehensive investigations are conducted into the chemical reactivity, Ti, Al, C, N vacancy sensitivity, and interfacial cleavage energies of their typical surfaces at primary dissociation stage under various elemental environments using first-principles calculations. The calculation results provide quantitatively explanation for the distinct evolution behaviors of ‘Extro-expansion & Inner-consumption’ of Ti2AlN and asynchronous dissociation of Ti3AlC2 in Al-rich conditions. In addition, the possible microstructural morphologies of the in-situ reinforcements in unexplored composites are predicted based on the thermodynamic and kinetic evolution of microstructures, which significantly influenced by the dissociation behavior of Ti2AlN and Ti3AlC2 precursors under specific chemical conditions. This study is expected to enhance the efficiency of optimizing microstructural configurations in composites, where Ti2AN and Ti3AlC2 as used precursors more effective than ever. [Display omitted] •Investigate chemical reactivity, monovacancy formation and cleavage energies of typical Ti2AlN and Ti3AlC2 surfaces.•Reveal ‘Extro-expansion & Inner-consumption’ dissociation in Ti2AlN/Al and asynchronous dissociation in Ti3AlC2/Al.•Reveal the influence of the primary dissociation behavior of the precursors on the in-situ microstructural configurations.•Predict possible microstructures’ morphologies based on Ti2AlN and Ti3AlC2 dissociation in Ti, Al, and TiAl alloys.•Highlight the importance of detailed dissociation behavior of the precursors in matrix for effective configuration design.