151. Structural and mechanical properties of magnesium aluminate nanoceramics under high pressure
- Author
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Zhiqiang Chen, Hailun Wang, Mingzhi Yuan, Hongliang Dong, Lingkong Zhang, Resta A. Susilo, Yanju Wang, Shun Wan, Bin Chen, Tingcha Wei, Jianing Xu, Dayong Tan, Tiecheng Lu, Zongqiang Feng, Tianlin Huang, Yan Chen, and Yuanjie Huang
- Subjects
010302 applied physics ,Phase transition ,Materials science ,Physics and Astronomy (miscellaneous) ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Nanoceramic ,Grain size ,Tetragonal crystal system ,Nanocrystal ,Structural stability ,0103 physical sciences ,Particle size ,Composite material ,0210 nano-technology ,Ductility - Abstract
Nanoceramics may have different structural and physical properties compared to their coarse-grained counterparts. Here, we report the high-pressure study of micro- and nano-crystalline MgAl2O4 in order to examine the effect of particle size on the structural stability. A reversible pressure-induced phase transition (cubic to tetragonal) is observed in MgAl2O4 nanocrystals under non-hydrostatic pressure at room temperature, in contrast to the previously reported structural transition of MgAl2O4 at high pressure and high temperature. It is also found that the compressed MgAl2O4 microcrystals do not fracture further below 60 nm, suggesting a plastic deformation mechanism transition. MgAl2O4 with a grain size above ∼60 nm exhibits normal cracking behaviors, but shows metal-like plastic deformation behaviors below this critical size. It is implied that combined ductility and strength can be achieved in nanoceramic MgAl2O4.
- Published
- 2020