Plane stress(Material property on block error)

[Emmanuel-324]

I am working with a 2D crystal plasticity problem and I am getting some stress response in the z direction but I want to treat my system as plane stress and strain.

I used the block below but I get

[elasticity_tensor_phase0]
    type = ComputeElasticityTensorCP
    C_ijkl = '2.906e5 1.87e5 1.87e5 2.906e5 1.87e5 2.906e5 1.142e5 1.142e5 1.142e5'
    fill_method = symmetric9
    base_name = phase0
  []
  [stress_phase0]
    type = ComputeMultipleCrystalPlasticityStress
    crystal_plasticity_models = 'trial_xtalpl_phase0'
    eigenstrain_names = 'eigenstrain_0'
    tan_mod_type = exact
    rtol = 1e-08
    base_name = phase0
  []
  
  [trial_xtalpl_phase0]
    type = CrystalPlasticityKalidindiUpdate
    number_slip_systems = 12
    slip_sys_file_name = input_slip_sys.txt
    crystal_lattice_type = BCC
    resistance_tol = 0.01
    r = 1.4             
    h = 6000            
    t_sat = 598.5        
    gss_a = 1.5         
    ao = 0.001           
    xm = 0.017             
    gss_initial = 600
    base_name = phase0
  []
  [eigenstrain_0]
    type = ComputeCrystalPlasticityThermalEigenstrain
    eigenstrain_name = eigenstrain_0
    deformation_gradient_name = deformation_gradient_1
    temperature = temperature
    thermal_expansion_coefficients = '12.8e-06 12.8e-06 12.8e-06'
    base_name = phase0
  []
  
  [./strain_phase0]
    type = ComputePlaneSmallStrain
    displacements = 'disp_x disp_y'
    base_name = phase0
  [../]

But I am getting this error

The following error occurred in the Problem 'MOOSE Problem' of type FEProblem.check_inp(moose_srv)
Material property 'phase0_strain_increment', requested by 'stress_phase0' is not defined on block 0check_inp(moose_srv)
Material property 'phase0_rotation_increment', requested by 'stress_phase0' is not defined on block 0check_inp(moose_srv)
Material property 'phase0_deformation_gradient', requested by 'stress_phase0' is not defined on block 0check_inp(moose_srv)\

I can't find where to solve it in the related classes. Initially, I had ComputeFiniteStrain and I had no material block issues

[GiudGiud]

Use Debug/show_material_props to see which materials are declaring what properties. Maybe it's just a missing phase0 prefix in one of the materials

[sapitts]

I would not use crystal plasticity with computePlaneSmallStrain. Crystal plasticity is fundamentally a plastic deformation model, and a small total strain is not a good match for plastic deformation: computeFiniteStrain is better.

While I have seen literature applying crystal plasticity in 2D, our models are not written for 2D use: the constitutive models assume a set of slip planes and slip directions in 3D space

[Emmanuel-324]

@sapitts is there a way I can restrict or make the eigenstrain in a specific(say feig_zz) direction zero?

[sapitts]

You could set the coefficient of the thermal expansion eigenstrain in the corresponding direction to zero, e.g. for zeroing out the zz eigenstrain, make the following change in the eigenstrain_0 block:

thermal_expansion_coefficients = '12.8e-06 12.8e-06 0.0'

[Emmanuel-324]

@sapitts Yes I tried making the thermal expansion eigenstrain in the z direction zero but that did not work as the solution never converged. Even reducing the order of magnitude in the z direction had similar convergence issues. for example:

thermal_expansion_coefficients = '12.8e-06 12.8e-06 12.8e-15 '

[sapitts]

Have you tried smaller eigenstrains in the x and y directions or incrementally increasing the eigenstrain values in x and y from a small starting value to the O(1e-6) shown here?