This research project focuses on the ’’’plastic deformation’’’ of silicate glasses. In practice, contacts, scratches and wear can indeed produce surface flaws on glass components, and these flaws drastically reduce the macroscopic ’’’strength’’’. The formation of such flaws can involve permanent deformation of the amorphous material at the micron-scale, the so-called micro-plasticity.
Micro-plasticity could also explain the difference between the surface energy and the fracture energy of glasses: plastic deformation occurring during failure would increase the energy dissipated in the fracture process.
These are the technological reasons why we ’’’investigate the plastic deformation of silicate glasses on a more fundamental viewpoint’’’.
Experimental investigations
Two experimental investigations of the plasticity of amorphous silica at the micron scale are presented: micropillar compression ( [1]) and microindentation coupled with Raman microspectroscopy ( [2]). Both experiment provide interesting data for the identification of a constitutive equation describing the plastic response of this material.
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Amorphous silica has been chosen since many aspects of its mechanical behavior has already been well documented, and also because the preparation of the pillars is simpler than for window glass...
The plasticity of amorphous silicates
People have dreamed for a perfectly plastic glass material for millennia... [4]
A constitutive equation
How can one assess these plastic deformation phenomena ? [5]
Publications
– [http://www.sciencedirect.com/science/article/pii/S1359645412004648 Plastic deformation and residual stresses in amorphous silica pillars under uniaxial loading], R. Lacroix, G. Kermouche, J. Teisseire and E. Barthel, ’’Acta Mater.’’ 60 (2012) 5555–5566.
– [http://hal.archives-ouvertes.fr/hal-00677258 Micro-pillar testing of amorphous silica], R. Lacroix, V. Chomienne, G. Kermouche, J. Teisseire, S. Queste and E. Barthel, ’’Int. J. Appl. Glass Sci.’’ 3 (2012) 36-43.
– [http://hal.archives-ouvertes.fr/hal-00258599/fr/ Density hardening plasticity and mechanical aging of silica glass under pressure: A Raman spectroscopic study], Vandembroucq D., Deschamps T., Coussa C., Perriot A., Barthel E., Champagnon B. and Martinet C., ’’J. Phys.: Condens. Matter’’ 20 (2008) 485221.
– [http://hal.archives-ouvertes.fr/hal-00260324/fr/ Mechanical modeling of indentation-induced densification in amorphous silica], G. Kermouche, E. Barthel, D. Vandembroucq and P. Dubujet, ’’Acta Mater.’’ 56 (2008) 3222-3228.
– [http://hal.archives-ouvertes.fr/hal-00002965/fr/ Raman Microspectroscopic Characterization of Amorphous Silica Plastic Behavior] A. Perriot, D. Vandembroucq, E. Barthel, V. Martinez, L. Grosvalet, Ch. Martinet and B. Champagnon, ’’J. Am. Ceram. Soc.’’ 89 (2006) 596-601.
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