article posted 22 Feb 2016
is a Mechanical Engineer (ENSAM, Paris), a Doctor in Ceramic Science (ENSCI, Limoges)
and full Professor of Glass Science and Solid Mechanics at the University of Rennes 1.
After obtaining an engineer diploma from the Ecole Nationale Supérieure d'Arts et Métiers,
TR gained his B. Sc (French DEA) from the University of Paris XIII, and his Ph.D
(French Doctorate) from the University of Limoges. After graduating he became a
Post-doctoral Fellow in the Government Industrial Research Institute of Nagoya
(then the NIRIN, Japan) for one year and a half. He then held a position as a CNRS
Researcher in Ceramics Science for four years, during which he spent several
periods of study leave in the department of Materials Science at the University of
Tokyo. In 1997, he was appointed Professor at the University of Rennes, where he
founded a laboratory (LARMAUR) devoted to the study of surface mechanics problems,
and flow and fracture in advanced glasses and ceramics. He is the author of
approximately 150 papers in scientific journals, 4 patents, and 5 book chapters.
He is also an associate Editor of the Journal of the American Ceramic Society.
Prizes and awards
French ceramic society prize, 1992.
CNRS Bronze medal, 1996.
Nominated to the Institute Universitaire de France, 2001.
Medal of the City of Rennes, 2001.
Asian Young Ceramist Conference in Tokai Award (AYCECT, Japan), 2006.
Yvan Peyches Award, French Academy of Sciences, 2007.
Professor Brahm Prakash Visiting Chair, Indian Institute of Science, Bangalore, India, 2009.
Adjunct Professor of the Chinese Academy of Science, SICCAS, Shanghai, China, 2009.
Otto Schott Research Award for "Outstanding research achievements in glass science", 2010.
Advanced Grant of the European Research Council "Pushing the Frontier of Glass Brittleness", 2012
Indentation-cracking behavior and structural characteristics:
Copper-borate, titanium-silicate, oxynitride, and chalcogenide glasses
Physics Institute (UMR UR1-CNRS 6251) - Mechanics and Glasses
University of Rennes 1, Rennes, France.
The indentation-cracking behavior of glasses from different chemical systems including
lead- and zinc-copper-borate, sodium-titanium-silicate, rare-earth-oxynitride, and
chalcogenide glasses, is revisited in the light of structural characteristics and elastic
properties. These glasses exhibit a great diversity of structural features, with much
different atomic bonding character, atomic packing density (Cg), crosslinking degree,
average coordination, and network energy to name a few key parameters. As Cg increases,
the indentation-cracking pattern evolves toward more lateral and radial cracking, and
Palmqvist cracking prevails, so that the available mechanical energy might dissipate
through the formation of more and longer radial cracks.
Copper borate glasses, with
large packing density and Poisson's ratio (up to 0.33) provide a remarkable illustration
of this evolution. On the contrary, sodium-titanium-silicate (with Poisson's ratio as
small as 0.18) turn out to fall in the property range where the driving force for indentation
cracking, whatever the cracking pattern of concern (radial, median, lateral), is relatively
limited and exhibit a good indentation damage resistance. Several unexpected trends are
observed. For instance, chalcogenide glasses are relatively soft but extremely brittle, and
silicon oxynitride glasses, in spite of a relatively high crosslinking exhibit a large Poisson's
ratio, which is favorable to lateral-radial cracking. This suggests some interesting structural
peculiarities in these latter systems.
This presentation is based on published works by S. Deriano, JP. Guin, P. Sellappan,
G. Scannel, and ZY Yao thanks to fruitful collaboration with Prof. L. Huang (RPI, USA),
Prof. L. Wondraczek (Univ. Jena, Germany), and Dr. A. Sharafat (Linnæus University,
Sweden), and on researches supported by the European Research Council, under the
Advanced Grant 320506.
1. G. Scannell, L. Huang, and T. Rouxel, " Elastic properties and indentation cracking behavior of Na2O-TiO2-SiO2 glasses", J. Non-Cryst. Sol., 429, 129-142 (3015).
2. Z.Y. Yao, D. Moncke, E.I. Kamitsos, P. Houizot, F. Célarié, T. Rouxel, and L. Wondraczek, "Structure and mechanical properties of copper-lead and copper-zinc borate glasses", J. Non-Cryst. Sol., 455, 55-68 (2016).
3. P. Sellappan, T. Rouxel, F. Celarie, E. Becker, P. Houizot, and R. Conradt, « Composition dependence of indentation deformation and indentation cracking in glass », Acta Mat., 61 5949-5965 (2013).
4. P. Sellapan, A. Sharafat, V. Keryvin, P. Houizot, T. Rouxel, J. Grins, and S. Esmaeilzadeh, "Elastic properties and surface damage resistance of nitrogen-rich (Ca,Sr)-Si-O-N glasses", J. Non-Cryst. Sol., 356 2120-26 (2010).
5. S. Dériano, T. Rouxel, M. Lefloch and B. Beneu, "Structural and mechanical properties of alkali-alkaline earth-silicate glasses", J. Phys. Chem. Glasses, 45 37-44 (2004).
6. J-P. Guin, T. Rouxel, J-C. Sangleboeuf, I. Melscoët, J. Lucas, "Hardness, toughness and scratchability of Ge-Se chalcogenide glasses", J. Am. Ceram. Soc., 85 1545-1552 (2002).
7. T. Rouxel, "Driving force for indentation cracking in glass: composition, pressure and temperature dependence", Phil. Trans. R. Soc. A, 373, 20140140 (2015).