Deviatoric stress-strain for crystal plasticity: "deviatoric_crystal_strength"

Input

This class implements crystal plasticity models described using deviatoric stress and strain measures. Material data include a polymorphic material model describing scalar response, a crystal elasticity model - polymorphic over the crystal symmetry - and a plasticity model.

In other words:

material_type (for scalar response, e.g. "eos" followed by EOS data)
crystal_type
minimum_angle_for_rotations (e.g. 1.0e-6)
fraction_of_plastic_work_going_to_heat (usually ~0.9 to 1.0)
number_of_slip_systems
For each (vectors referring to natural crystal orientation):
   plane_normal_vector
   slip_direction_vector
   strain_increment (real 6-vector: 3x3 matrix in Voigt notation)
obstacle_cross_term_matrix (square, dimension = number of slip systems)

The minimum angle is used to decide when material rotation can be ignored.

Elasticity types

In all cases, each elasticity parameter is a polymorphic function as described below.

Elasticity functions

State

material_state
elastic_strain_deviator (real 6-vector: 3x3 matrix in Voigt notation)
rotation matrix from crystal to problem (real 6-vector: 3x3 matrix in Voigt notation)
defect_density obstacle_density (mediating and impeding plasticity)