A St. Venant Kirchhoff cubic material is one where
|
| (1) |
where S is the 2nd Piola-Kirchhoff stress tensor and E is the Green-Lagrange strain tensor. The modulus tensor is
![ℂ = 2μ𝕀sym + β1 ⊗ 1+ (α - 2μ- β)[a ⊗ a ⊗ a⊗ a + b⊗ b ⊗ b⊗ b+ c ⊗ c⊗ c⊗ c] .](csvk1x.png) | (2) |
Here α, β, and γ are the elastic constants and a, b, and c are the unit vectors in the cubic crystal directions.