Correlation between the dynamic fracture surface energy GID and the amount of created surface
For rapid crack propagations.two kinds of material behavior have been observed.Typically,most materials show an increase of the fracture energy with the crack tip velocity.However.there do exist a few materials for which the fracture energy tends to decrease with the velocity 1,2.They are viscoplastic blend materials like polymers such as rubber toughened polymethylmethacrylate (RT-PMMA).For these materials,crack tips are seen to propagate at the same velocity whatever the loading rate is (or strain energy release rate).This critical velocity has been shown to be the crack branching velocity,at least at a macroscopic scale.Our study shows that the classical approach which considers that the amount of created surface during the propagation can be approximated as the sample thickness multiplied by the crack length is not appropriate.Indeed.this study shows that the exact fracture surface roughness has to be included in the amount of created surface in order to establish an intrinsic material fracture energy GID.As the fracture surface roughness depends on the scale at which the sample is observed.a self-affine model widely used for fracture surfaces is introduced 3,4.This statistical geometrical model of the fracture surface with two parameters.a Hurst exponent and a topothesy is shown to be effective and provides a better estimate of the intrinsic surface fracture energy.
Dynamic fracture rapid crack propagation polymers energy release rate. self-affine analysis Hurst exponent
Jean-Benoit Kopp Jean Schmittbuhl Jian Lin Christophe Fond
ICube-2 rue Boussingault,F67000 Strasbourg Ecole et Observatoire des Sciences de la Terre,5 Rue René Descartes,F67000 Strasbourg
国际会议
北京
英文
1-9
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）