Isotropic Material

Here is very simple LaTeX equation for testing:

[math]\displaystyle{ E = mc^2 }[/math]

This material is a small strain, linear elastic material. The stress is related to strain by

[math]\displaystyle{ \sigma_{ij} = \bigl(\lambda\epsilon_{ii} - 3K\alpha T\bigr)\delta_{ij} + 2G\epsilon_{ij} }[/math]

where λ is the Lame, K is bulk modulus, α is thermal expansion coefficient, T is temperature difference, and G is shear modulus.