Inelastic behaviour of ceramic-matrix composites
- 作者：Baste ; Sté ; phane
- 关键词：A. Ceramic-matrix composites ; B. Modelling ; Non-linear behaviour ; Matrix cracking ; C. Anisotropy ; Damage mechanics ; Elastic properties ; D. Ultrasonics
- 刊名：Composites Science and Technology
- 出版年：2001
- 期刊代码：19_02663538
- 类别：ms
- 出版时间：November - December, 2001
- 卷：61
- 期：15
- 页码：2285-2297
- 文件大小：577 K
摘要
A methodology for the formulation and identification of the constitutive laws of ceramic-matrix composites is summarised. It relies on an anisotropic damage evaluation that accurately separates the effects of the various damage mechanisms on the non-linear behaviour. A mixed approach takes into account the basic strain and damage mechanisms by using a homogenisation method that provides the relationship between the mechanical response and the intensity of damage in the individual modes. That leads to a non-arbitrary choice of internal variables in the macroscopic constitutive relationships. A successive process of prediction/experimental-data confrontation allows the optimal determination of the evolution laws of those internal variables. This methodology is illustrated on various behaviours of various CMCs; several crack arrays, tilted cracks, tensile test, cyclic loading, off-axis solicitation, in 1D SiC–SiC, 2D C–SiC, 2D C/C–SiC ceramic-matrix composites. Predictions of the three-dimensional changes in elasticity and of the inelastic strains are shown to compare favourably with experimental data measured with an ultrasonic method.