New Computational Framework for Modeling Porous Materials
Abstract
The U.S. Air Force makes use of a large array of materials, many of which are quite ductile and may exhibit anisotropy and initial defects. While many efforts have been devoted to modeling such systems, most of the ductile models are empirical. For most advanced models involving 6-D yield surfaces, form analysis has not been done. In this effort, we deduced new mathematical results that enable to recognize that all the widely used isotropic models are in fact homogeneous polynomials of J2 and J3, the invariants of the stress deviator. This had very important implications, one of them being the possibility to obtain explicit expressions in terms of the components of the stress tensor of anisotropic extensions of these models, which are part of the material libraries of commercial and government codes. It was shown that these models are in fact of the same form with anisotropy coefficients that are not independent and impose un-physical couplings between shear and normal stress properties. Most importantly, for the first-time analytical expressions of the anisotropy coefficients of these criteria were derived. The new mathematical results lead to better understanding and analysis of anisotropic materials data sets, the correlations of anisotropy coefficients to physical properties/microstructures, reliability of parameter identification, and ultimately the fidelity of numerical simulations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 10, 2021
- Accession Number
- AD1153239
Entities
People
- Oana Cazacu
Organizations
- University of Florida