Free volume model: high temperature deformation of a Zr based bulk metallic glass

Marc Bletry (1, 2) , Pierre Guyot (2) , Jean-Jacques Blandin (3) , Jean-Louis Soubeyroux (4)

1 CRETA - Consortium de Recherches pour l'Emergence des Technologies Avancées
2 LTPCM - Laboratoire de thermodynamique et physico-chimie métallurgiques
3 GPM2 - Génie physique et mécanique des matériaux
4 Laboratoire de Cristallographie

Homogeneous deformation of a zirconium based bulk metallic glass is investigated in the glass transition range. Compression tests at different temperatures and strain rates have been conducted. The mechanical behavior is analyzed in the framework of the free volume model, taking into account the dependence of the flow defect concentration with the deformation. The activation volume is evaluated and allows the gathering of the viscosity data (for the different strain-rates and temperatures) on a unique master curve. It is also shown that, due to the relation between flow defect concentration and free volume, it is not possible to deduce the equilibrium flow defect concentration directly from mechanical measurements. However, if this parameter is arbitrary chosen, mechanical measurements give access to the other parameters of the model, these parameters being of the same order of magnitude for the studied alloy when compared with other metallic glasses

Mots clés: Metallic glasses; high temperature deformation; plastic deformation; free volume model

Domaines: Matériaux

Marc Bletry, Pierre Guyot, Jean-Jacques Blandin, Jean-Louis Soubeyroux. Free volume model: high temperature deformation of a Zr based bulk metallic glass. Acta Materialia, 2006, 54, pp.1257-1263. ⟨10.1016/j.actamat.2005.10.054⟩. ⟨hal-00264968⟩