Calculations of single crystal elastic constants for yttria partially stabilised zirconia from powder diffraction data

Journal Article · Thu Aug 07 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4891714· OSTI ID:22320368

Lunt, A. J. G.,; Xie, M. Y.; Baimpas, N.; Korsunsky, A. M. ^[1]; Zhang, S. Y.; Kabra, S.; Kelleher, J. ^[2]; Neo, T. K. ^[3]

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1. Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ (United Kingdom)
2. ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Harwell, Oxford OX11 0QX (United Kingdom)
3. Specialist Dental Group, Mount Elizabeth Orchard, 3 Mount Elizabeth, #08-03/08-08/08-10, Singapore 228510 (Singapore)

Yttria Stabilised Zirconia (YSZ) is a tough, phase-transforming ceramic that finds use in a wide range of commercial applications from dental prostheses to thermal barrier coatings. Micromechanical modelling of phase transformation can deliver reliable predictions in terms of the influence of temperature and stress. However, models must rely on the accurate knowledge of single crystal elastic stiffness constants. Some techniques for elastic stiffness determination are well-established. The most popular of these involve exploiting frequency shifts and phase velocities of acoustic waves. However, the application of these techniques to YSZ can be problematic due to the micro-twinning observed in larger crystals. Here, we propose an alternative approach based on selective elastic strain sampling (e.g., by diffraction) of grain ensembles sharing certain orientation, and the prediction of the same quantities by polycrystalline modelling, for example, the Reuss or Voigt average. The inverse problem arises consisting of adjusting the single crystal stiffness matrix to match the polycrystal predictions to observations. In the present model-matching study, we sought to determine the single crystal stiffness matrix of tetragonal YSZ using the results of time-of-flight neutron diffraction obtained from an in situ compression experiment and Finite Element modelling of the deformation of polycrystalline tetragonal YSZ. The best match between the model predictions and observations was obtained for the optimized stiffness values of C11 = 451, C33 = 302, C44 = 39, C66 = 82, C12 = 240, and C13 = 50 (units: GPa). Considering the significant amount of scatter in the published literature data, our result appears reasonably consistent.

• OSTI ID: 22320368
• Journal Information: Journal of Applied Physics, Vol. 116, Issue 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CERAMICS
COMPRESSION
DEFORMATION
FLEXIBILITY
MONOCRYSTALS
NEUTRON DIFFRACTION
PHASE TRANSFORMATIONS
PHASE VELOCITY
POLYCRYSTALS
PRESSURE RANGE GIGA PA
PROSTHESES
SIMULATION
SOUND WAVES
STRAINS
STRESSES
TEMPERATURE DEPENDENCE
TIME-OF-FLIGHT METHOD
YTTRIUM OXIDES
ZIRCONIUM OXIDES