In anisotropic materials, Young's modulus may have different values depending on the direction of the applied force with respect to the material's structure.
However, wood is an anisotropic material with respect to heat flow.
Polarized light does interact with anisotropic materials, which is the basis for birefringence.
This is to say, the polarizability of anisotropic materials is not equivalent in all directions.
Rotating an anisotropic material results in a variation of its elasticity tensor.
However, in anisotropic materials, this relationship does not strictly hold.
In all cases the anisotropic material is first deposited on the base substrate.
Walpole applied the theorems (4.16) to the case of anisotropic materials in a later paper.
Another form of birefringence is observed in anisotropic elastic materials.
Some anisotropic materials have one or more Poisson ratios above 0.5 in some directions.