OOF2: The Manual
Name
IsotropicRank4Tensor — Representations of an isotropic 4th rank tensor.
Subclasses
Subclasses are listed as they appear in the GUI and (in parentheses) as they appear in scripts.

Cij (
IsotropicRank4TensorCij
)  Explicit representation in terms of tensor components. 
Lame (
IsotropicRank4TensorLame
)  Isotropic rank 4 tensor in terms of Lame coefficients. 
E and nu (
IsotropicRank4TensorEnu
)  Isotropic rank 4 tensor in terms of Young's modulus and Poisson's ratio. 
Bulk and Shear (
IsotropicRank4TensorBulkShear
)  Isotropic rank 4 tensor in terms of bulk and shear moduli.
Description
The IsotropicRank4Tensor
represents rank 4
tensor properties which are rotationally invariant, such as
isotropic elasticity. The isotropic rank 4 tensor has two
independent components, as shown in Figure 6.56. Because the elasticity
literature uses many different representations of these two
components, OOF2 allows you to enter the tensor in a variety of
formats.
Note  

The word “rank” has different meanings in different fields. Here it means the number of indices on a tensor. is a rank 4 tensor. 