@article{d1963ec6f67e412587c3bb695de2fe4c,
title = "In situ quantitative three-dimensional characterisation of sub-indentation cracking in polycrystalline alumina",
abstract = "The three-dimensional deformation beneath a Vickers indentation in polycrystalline alumina has been measured, in situ, by digital volume correlation of high resolution synchrotron X-ray computed tomographs. The displacement fields at the peak indentation load and after unloading are used to study the shape and orientation of sub-surface cracks induced by the indentation; lateral cracking due to residual stresses, bounded by a system of radial cracks, is revealed. For the first time, it is shown that radial cracks have mixed mode opening displacements, which are affected by the relaxation of residual stresses via lateral cracking. This novel technique may find applications in the study of surface damage by abrasive wear in brittle materials.",
keywords = "alumina, crack, digital volume correlation, indentation",
author = "Yelena Vertyagina and Mahmoud Mostafavi and Christina Reinhard and Robert Atwood and Marrow, {T. James}",
note = "Funding Information: This work was carried out with the facilities of the Diamond Light Source; the authors acknowledge the beam time award at the Joint Engineering, Environmental and Processing (I12) beamline (Experiment EE7730) and the help of Dr D.M. Collins, Dr H. {\c C}etinel and Mr S. Barhli to conduct the experiment. M.M. and T.J.M. gratefully acknowledge the support of Oxford Martin School, M.M. acknowledges the support of Linacre College, Oxford through a Junior Research Fellowship and Y.V. acknowledges the support of EDF Energy UK. The Manchester X-Ray Imaging Facility (Dr S.A. McDonald and Professor P.M. Mummery) are thanked for the loan of the loading rig. Professor R.I. Todd, The University of Oxford, is thanked for valuable discussions. Almath Crucibles are thanked for supplying the alumina.",
year = "2014",
month = oct,
doi = "10.1016/j.jeurceramsoc.2014.04.002",
language = "English",
volume = "34",
pages = "3127--3132",
journal = "Journal of the European Ceramic Society",
issn = "0955-2219",
publisher = "Elsevier BV",
number = "12",
}