Programme

P.42 -- Poster, NCTP-43

Date: Wednesday, 1 August 2018

Time: 08:30 - 10:00

Structural transformation in Al2O3 under densification

Le Thi Chinh*, Le Van Vinh

School of Engineering Physics, Hanoi University of Science and Technology, Hanoi, Vietnam.

Molecular dynamics simulations of Al2O3 system have been used to investigate the pressure-induced structural transformation. The sample of Al2O3 containing 5000 atoms was heated at 5000 K for 100 ps and then cooled down to 3500 K for 100 ps. This sample was continuously cooled down to 300 K with the cooling rate of 1×1013 K/s upon the pressure of 0, 5, 10, 15, 20, 30, 45 and 60 GPa. With increasing pressure above 5 GPa, O atoms are more ordered than Al atoms. By using common neighbour analysis method, we found that, firstly, O atoms form to hcp clusters. With further increasing pressure, O atoms form both fcc and hcp crystals. The formation of crystalline O lattices leads to Al atoms which become more structural order. The structural transformation has been discussed and visualized in details.

Presenter: Le Thi Chinh