Purpose: The goal of this investigation was to characterize the compliance properties in selected polymers used for temporary (provisional crown and bridge) applications. Method: Polymethyl methacrylate (PMMA)- and polyethyl methacrylate (PEMA)-based JET and TRIM II were investigated along with two bisacryl composite resins (LUXATEMP and PROTEMP 3 GARANT). Rectangular samples of the resins were...

Analysis of large deformation of elastic-viscoplastic materials has been performed in this paper using the finite element method with the arbitrary Lagrangian-Eulerian description. An overstress type viscoplastic model using the internal variable approach in a rotated stress-strain space characterizes the material. Stable and efficient integration techniques for the viscoplastic relations are d...

We consider a class of abstract nonlinear evolution systems arising in the study of quasistatic frictionless contact problems for elastic-viscoplastic materials. The variational analysis of such systems, including existence and uniqueness results as well as some properties concerning the behavior of the solution, has been done in 12]. In this paper we consider numerical approximations of this c...

Simulations of viscoplastic materials are traditionally governed by continuum mechanics. The viscous behavior is typically modeled as an internal force, defined by diverse quantities. This work introduces a fluid model to simulate the viscoplastic effect of solid materials, such as plastic, wax, clay and polymer. Our method consists in modeling a solid object through a non-Newtonian fluid with ...

Micro-macro schemes contain two important steps. First, the localization process must link the fields inside the inclusion to those applied in the infinite matrix. Secondly, an averaging process is used to derive the macroscopic behavior. For elastic viscoplastic materials, there is no exact solution for the first step. In this work, we adopt the interaction law proposed in [2]. By comparison w...

Dynamic pore collapse in porous materials is studied by analyzing the finite deformation of an elastic/viscoplastic spherical shell under impulsive pressure loading. Effects of dynamic loading rate, pore size, initial porosity, strain-rate sensitivity, strain hardening, thermal softening, and mass density of the matrix material on the pore collapse process are examined and results are compared ...

We consider numerical approximations of a class of abstract nonlinear evolutionary systems arising in the study of quasistatic frictional contact problems for elastic-viscoplastic materials. Both spatially semi-discrete and fully discrete schemes are analyzed with the nite element method employed to discretize the spatial domain. Strong convergence of both approximations is established under mi...