Structural and mechanical properties of Al2O3.2SiO2 glass: Insights from molecular dynamics simulations

The Tensile Deformation of Multiphase Al2O3: Insights from Molecular Dynamics Simulations

“…This may relate to the growth and coalescence of voids in the disordered structure, which occur in oxide systems under tensile deformation. [22,23] Figure 7 shows the radii distributions (RDs) of the simplexes at the different strains. In both γand αphases, the RDs have two peaks, with the main peak located at 1.58 Å and the small peak located at 1.33 Å for OAl simplexes.…”

“…This may relate to the growth and coalescence of voids in the disordered structure, which occur in oxide systems under tensile deformation. [ 22,23 ]…”

“…The uniaxial tensile tests were performed on these Al 2 O 3 samples following a procedure that is described in detail in previous publications. [ 23,29 ] Per this procedure, a stepwise displacement of the atomic positions, , , and , was worked by the tensile load, in which ( x , y , z ) and ( x 0 , y 0 , z 0 ) are the displaced and previous positions of an atom at each time step, respectively, γ = 0.0001 is the applied strain, and ν ≈ 0.22 is an approximation of Poisson's ratio. Tensile loading was performed at a temperature of 300 K in the constant number–volume–temperature (NVT) ensemble.…”

“…MD simulations are a useful approach to investigate the structural transformation and deformation mechanisms of materials because they provide direct access to the trajectory of atoms at any simulation time, especially on oxide systems. [19][20][21][22][23] The MD simulations interpret that the role of amorphous Al 2 O 3 particles in a soda-lime silica glass matrix is to store strain energy and improve the toughness of the composite material. [19] Multiphase Al 2 O 3 samples are simulated using molecular dynamics method.…”

“…[ 20,21 ] As the network structure of oxide systems consists of structural MO x (where M = Si, Al,…) units, with each MO x unit linked to its neighboring units via a bridging O, the stretching and breakage of MO bonds cause voids to grow and coalesce under tensile deformation. [ 22,23 ] The voids and atoms located near the voids have been detected by simplex analysis in Al 2 O 3 ·2SiO 2 glass, in which crack propagation occurs when the large simplexes overlap; in this case, O atoms belonging to these large simplexes play an important role in simplex growth and coalescence. [ 23 ] Thus, simplex analysis can be used to investigate microscopic cracks, where the early stages of delayed fracturing involve the interaction and coalescence of nearby flaws in dense Al 2 O 3 .…”