Dynamic Fragmentation of Brittle Solids: A Multi-Scale Model
Résumé
Modeling dynamic fragmentation of brittle materials usually implies to choose between a discrte description of the number of fragments and a continuum approach with damage variables. A damage model that can be used in the whole range of loadings (from quasi static to dynamic ones) is developed. The deterministic or ptobabilistic nature of fragmentation is discussed. Qualitative and quantitative validations are given by using a real-time visualization configuration for analyzing the degradation kinetics during impact and a moiré technique to measure the strains in a ceramic tile during impact. Finally, a closed-form solution of the change of the number of fragments with applied stress gives a way of optimizing the microstructure of ceramics for armor applications.