research

Universal (controllable) deformations of an elastic solid are those deformations that can be maintained for all possible strain-energy density functions and suitable boundary tractions. Universal deformations have played a central role in nonlinear elasticity and anelasticity. However, their classification has been mostly established for homogeneous isotropic solids following the seminal works of Ericksen. In this paper, we extend Ericksen's analysis of universal deformations to inhomogeneous compressible and incompressible isotropic solids.

Phononic materials: controlling elastic waves in solids

Ignacio Arretche (ia6 [at] illinois.edu), Ganesh Patil (gupatil2 [at] illinois.edu), Kathryn Matlack (kmatlack [at] illinois.edu)

Dear Colleagues,

I am writing to share with you my article titled, "Precipitation during creep in magnesium-aluminum alloys" , which has been published in the journal Continuum Mechanics and Thermodynamics. 

Lightweight magnesium-aluminum alloys show significant tension-compression asymmetry under creep loading. This work offers an explanation of this phenomenon.

Link to the article: https://rdcu.be/ct4zi

Dear iMechanicians, I would like to share our recent work on a drop confined by two adhesive graphene sheets (as illustrated below). 

Amit Acharya

A formal methodology for developing variational principles corresponding to a given nonlinear
pde system is discussed. The scheme is demonstrated in the context of the incompressible
Navier-Stokes equations, systems of first-order conservation laws, and systems of Hamilton-
Jacobi equations.

Amit Acharya

To appear in J. Mech. Phys Solids

Amit Acharya

An action functional is developed for nonlinear dislocation dynamics. This serves as a first step
towards the application of effective field theory in physics to evaluate its potential in obtaining
a macroscopic description of dislocation dynamics describing the plasticity of crystalline solids.
Connections arise between the continuum mechanics and material science of defects in solids,
effective field theory techniques in physics, and fracton tensor gauge theories.

The scheme that emerges from this work for generating a variational principle for a nonlinear
pde system is general, as is demonstrated by doing so for nonlinear elastostatics involving a stress
response function that is not necessarily hyperelastic.