Tanguy ROUXEL,

Professor, Member of the Institute Universitaire de

Affiliation:

LARMAUR (Applied Mechanics Laboratory), FRE-CNRS 2717 Bat. 10B, campus de Beaulieu, 35042 cedex, France.

Tel. +33 (0)2 23 23 67 18 Fax. +33 (0)2 23 23 16 00 E-mail: [email protected] www.larmaur.univ-rennes1.fr

Brief personal history Tanguy Rouxel gained his B. Sc (French DEA) in Mechanics of Materials from the University of XIII, and his Ph.D (French Doctorate) in Ceramic Science from the . 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. Dr. Rouxel then held a position as a CNRS Researcher in the Ecole Nationale Supérieure de Céramiques Industrielles for four years, during which he spent several periods of study leave, in the department of Materials Science at the University of Tokyo, and in the Glasses and Ceramics laboratory in the University of Rennes (France). In 1997, Dr. Rouxel was appointed Professor at the University of Rennes, where he is presently leading a new research laboratory (the LARMAUR) devoted to the study of surface mechanics problems, and flow and fracture in advanced glasses and ceramics.

Recently published papers: 1. H. Shang and T. Rouxel, "Creep Behavior of Soda-Lime Glass in the 100-500 K Temperature Range by Indentation Creep Test", J. Am. Ceram. Soc., 88 [9] 2625-2628 (2005). 2. S. Yoshida, J-C. Sangleboeuf and T. Rouxel, "Quantitative evaluation of indentation- induced densification in glass", J. Mat. Res., 20 3404-3412 (2005). 3. H. Shang, T. Rouxel, M. Buckley and C. Bernard, "Viscoelastic Behavior of Soda-Lime- Silica Glass Determined by High Temperature Indentation Test", J. Mat. Res., 21 632- 638 (2006). 4. V.Keryvin, C. Bernard, J-C. Sangleboeuf, Y. Yokoyama and T. Rouxel, " Toughness of Zr55Cu30Al10Ni5 bulk metallic glass for two oxygen levels", J. of Non-Cryst. Sol., 352 [26-27], 2863-2868 (2006).

AYCeCT – Gifu (Japan) Oct. 26-28, 2006

Designing glasses to meet specific mechanical properties

Tanguy Rouxel

Laboratoire de Recherche en Mécanique Appliquée de l'Université de Rennes (LARMAUR), FRE-CNRS 2717, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex

Glasses are brittle materials. Nevertheless, both the amount and the diversity of available glasses are quickly rising. At every stage of the life of a glass specific mechanical properties are required. These properties should allow the elaboration and the shaping stages with industrial means and warrant a good durability in service. For instance, the elastic moduli of inorganic glasses cover a wide range. Young's modulus (E) extends from 5 GPa for glassy ice to 180 for an oxynitride glasses and 365 GPa for a metallic glass and Poisson's ratio (ν) is as low as 0.1 for an oxycarbide glass and as high as 0.4 for a bulk metallic glass. Beside the essential role of elastic properties for materials selection in mechanical design, macroscopical elastic characteristics (E,ν) provide an interesting way to get insight into the short- and medium-range orders existing in glasses. In particular, ν, the packing density (Cg) and the glass network dimensionality appear to be strongly correlated. Networks consisting primarily of chains and layers units (chalcogenides, low Si-content silicate glasses) correspond to ν>0.25 and Cg>0.56, with maximum values observed for metallic glasses (ν~0.4 and Cg>0.7). On the contrary, ν<0.25 is associated to a highly cross- linked network with a tri-dimensional organization resulting in a low packing density. The same holds also for the viscosity, fracture toughness and hardness, which take very different values from one glass to another, either within a given glass compositional system or between various glass families. Besides, interestingly, the mechanical properties of glasses bring a new light on the short and medium range orders of the glass atomic networks.

Tanguy ROUXEL ************************************ Applied Mechanics Laboratory (LARMAUR) FRE-CNRS 2717, Bat 10B University of Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France. Tel: From within France: 02 23 23 67 18 From abroad: 33 2 23 23 67 18 Fax: 02 23 23 61 11 www.larmaur.univ-rennes1.fr