Modeling the Impact Behavior of AD85 Ceramic Under Multi-Axial Loading

摘要

This report presents an advanced constitutive model to describe the complexbehavior of ceramic materials under impact loading conditions. The governing equations utilize a set of microphysically based constitutive relationships to model deformation and damage processes in a ceramic. The total strain is decomposed into elastic, plastic, and microcracking components. The model parameters for AD85 ceramic were determined using the data from split Hopkinson bar (SHB) and bar-on-bar experiments under uniaxial stress state and plate impact experiment under uniaxial strain state. To further validate the generality of the model parameters, modeling of a diagnostic ballistic experiment in which a steel projectile impacted an AD85 ceramic front-faced thick aluminum plate was considered. In this experiment, stress histories were measured in the target by embedded manganin and carbon stress gauges. The results from the numerical simulations of the ballistic experiment using a shock wave propagation based finite element code successfully matched the measured stress history.