3D Continuum Damage Mechanics Model with Permanent Strain
Most currently available material models for composites do not allow for permanent strain. For applications such as ballistic containment and energy absorption applications, this results in under predicting material performance. This study extends the Matzenmiller, Lubliner and Taylor (MLT) model, a continuum damage mechanics (CDM) based constitutive model for unidirectional composites, to 3D solid elements, and enhances it with permanent strain capability. The model was implemented into the commercially available finite element code LS-Dyna. The model was validated with 3-point bend experiment. It was then used to simulate ballistic impact tests of an aluminum projectile against a glass fiber composite plate. As shown in the results below, this provides significant improvement in prediction of material performance
The article analyzes the results of the application of the equation for describing creep of metals in various temperature and force ranges with the aid of the same numerically specified constants. An experimental evaluation is made of the possibility of describing from the same positions the regularities of instantaneous and short-term deformation, creep, stress relaxation, and creep limit.