The plug is most easily seen in the third photograph, as the undeformed portion of the cylinder. Simulations of the impact event using a Material Point code. An axisymmetric calculation was perfomed, and positions of material points plotted in red. The horizontal axis has units of cm. Viscoelastic, Viscoplastic Constitutive Models for Polymers Polymeric materials are used in many composite materials, including high explosives.
Polymers typically exhibit complex behavior, including rate-dependence and inelasticity.
Viscoelastic constitutive formulations are being investigated as characterizations of a class of binders used in high explosives. It is interesting to note that upon retrieval of the specimen shown above, it had returned to its initial configuration. The constitutive modeling also exhibits this feature. This polymer modeling effort is also strongly coupled to an experimental investigation currently being conducted in the Materials Science Technology Division at Los Alamos. Because the resin exhibits large permanent deformations, a viscoplastic constitutive formulation is being used to model it.