Oxygen diffusion in 4, 8 or 14mol% yttria-stabilized zirconia, subjected to uniaxial stresses in the [100], [110] and [111] directions, was investigated by molecular dynamics simulation. For uniaxial stress in the [100] direction, oxygen diffusion in 4 or 8mol% yttria-stabilized zirconia was facilitated in the tensile direction and impeded in the compressive direction; without altering the total diffusion. This was attributed to the elastic recovery force. In 14mol% yttria-stabilized zirconia, oxygen diffusion remained unchanged regardless of the stress; probably due to the high yttria concentration. For tensile stresses in the [110] or [111] directions, oxygen diffusion was also increased in the tensile direction. This was attributed to an improvement in oxygen diffusion in the <100> direction, caused by the stress component in that direction. A tensile stress component in the <100> direction could therefore facilitate oxygen migration in yttria-stabilized zirconia at lower yttria concentrations.

Molecular Dynamics Study on Oxygen Diffusion in Yttria-Stabilized Zirconia Subjected to Uniaxial Stress in Terms of Yttria Concentration and Stress Direction. Araki, W., Arai, Y.: Solid State Ionics, 2010, 181[33-34], 1534-41