Analysis and Characterization of Damage Utilizing an Orthotropic Generalized Composite Material Model Suitable for Use in Impact ProblemsThe need for accurate material models to simulate the deformation, damage and failure of polymer matrix composites under impact conditions is becoming critical as these materials are gaining increased usage in the aerospace and automotive communities. In order to address a series of issues identified by the aerospace community as being desirable to include in a next generation composite impact model, an orthotropic, macroscopic constitutive model incorporating both plasticity and damage suitable for implementation within the commercial LS-DYNA computer code is being developed. The plasticity model is based on extending the Tsai-Wu composite failure model into a strain hardening-based orthotropic plasticity model with a non-associative flow rule. The evolution of the yield surface is determined based on tabulated stress-strain curves in the various normal and shear directions and is tracked using the effective plastic strain. To compute the evolution of damage, a strain equivalent semi-coupled formulation is used in which a load in one direction results in a stiffness reduction in multiple material coordinate directions. A detailed analysis is carried out to ensure that the strain equivalence assumption is appropriate for the derived plasticity and damage formulations that are employed in the current model. Procedures to develop the appropriate input curves for the damage model are presented and the process required to develop an appropriate characterization test matrix is discussed
Document ID
20160010260
Acquisition Source
Glenn Research Center
Document Type
Conference Paper
Authors
Goldberg, Robert K. (NASA Glenn Research Center Cleveland, OH United States)
Carney, Kelly S. (NASA Glenn Research Center Cleveland, OH United States)
DuBois, Paul (George Mason Univ. Fairfax, VA, United States)
Hoffarth, Canio (Arizona State Univ. Tempe, AZ, United States)
Rajan, Subramaniam (Arizona State Univ. Tempe, AZ, United States)
Blankenhorn, Gunther (Livermore Software Technology Corp. CA, United States)
IDRelationTitle20160002089See AlsoAnalysis and Characterization of Damage Utilizing an Orthotropic Generalized Composite Material Model Suitable for Use in Impact Problems