research

Paper Accepted for Publication in International Journal for Numerical Methods in Engineering

Consistent and stable meshfree Galerkin methods using the virtual element decomposition

A. Ortiz-Bernardin, A. Russo, N. Sukumar

Abstract

    The stress concentration induced by fretting fatigue was studied with a simple "Crack Analogue" model (CA) by the MIT group of Suresh in the late 1990's, which was then "improved" by the present author to take into account simply both contact loads and bulk stresses loads, and even the case of finite stress concentration in the so-called "Crack Like Notch Analogue" (CLNA) model.

To appear in Journal of Elasticity

A continuum mechanical theory of fracture without singular fields is proposed. The primary
contribution is the rationalization of the structure of a `law of motion' for crack-tips, essentially
as a kinematical consequence and involving topological characteristics. Questions of compatibility
arising from the kinematics of the model are explored. The thermodynamic driving force
for crack-tip motion in solids of arbitrary constitution is a natural consequence of the model.
The governing equations represent a new class of pattern-forming equations.

Highly porous alumina-zirconia ceramics were produced by adding space-holder materials during freeze casting. To increase the strength of porous ceramics, different amounts of nanoadditives (silicon carbide-SiC, silica-SiO₂, and multi-wall carbon nanotubes-CNTs) were added. Space-holder materials were removed by preheating, and solid samples were produced by sintering. Up to 68% porosity was achieved when 40% space-holder was added to the solid load of slurry. Wall thicknesses between pores were more uniform and thinner when nanoadditives were added.

2D materials are fascinating for numerous reasons. Their geometrical and mechanical characteristics along with other associated physical properties have opened up fascinating new application avenues ranging from electronics, energy harvesting, biological systems among others. Due to the 2D nature of these materials, they are known for their unusual flexibility and the ability to sustain large curvature deformations. Further, they undergo noticeable thermal fluctuations at room temperature.

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