Multiple Scale Analysis of Damage and Texture Evolution in Real Heterogeneous Materials

摘要

A combined experimental-computational approach has been pursued to study the evolution of microscopic damage to cause failure in heterogeneous composite and porous materials. The experiments include interrupted testing methods where the load is halted prior to fracture. Microstructures in the severely necked region are examined in 3D using a serial sectioning method. Characterization functions are generated and sensitivity analysis is conducted to explore the influence of morphological parameters on damage. A novel microstructural Voronoi cell finite element model (VCFEM) is developed to simulate the evolution of damage in microstructures. The model is capable of efficient and accurate prediction of microstructure evolution and particle cracking. An adaptive multi-level methodology is developed to create a hierarchy of computational sub-domains with varying resolution for multiple scale problems. It concurrently predicts evolution of variables at the structural scales by conventional FEM and at the microstructural scales by VCFEM.