FeCrAl Isotropic Plasticity Update

Calculates the plastic strain as a function of strain rate for FeCrAl cladding. Note: This material must be run in conjunction with ComputeMultipleInelasticStress.

Description

FeCrAlPlasticityUpdate calculates the plastic strain for FeCrAl cladding materials as a function of temperature. This material which must be run in conjunction with ComputeMultipleInelasticStress calculates the plastic strain for FeCrAl alloys. The material model inherits from IsotropicPlasticityStressUpdate and sets the yield_stress_function internally based upon temperature. The yield stress as a function of temperature is a piecewise linear function based upon the experimental data of Yamamoto et al. (2015).

Yamamoto et al. (2015)`s data only covers temperatures ranging from 300 to 1000 K. Based on research by Yano et al. (2016) on other ferritic and martensitic steels, there are distinct temperature dependent regions (low, mid, high) of the ultimate tensile strength (UTS). In the low temperature region the UTS drops relatively slowly with increasing temperature. In the midrange temperatures there is a rapid decrease in the UTS as temperature increases. The high temperature region results in a slow reduction of the UTS to approximately zero at the melting point. Using these observations on other alloys, an additional data point of a UTS of zero was added to Yamamoto's data at the melting point of FeCrAl alloys (1773 K). Since the yield stress approaches the UTS at the midrange temperatures, the yield stress is also set to zero at the melting point as shown in the table below.

The minimum or maximum yield stress is used if the temperature is outside the temperature bounds presented here. For example if the temperature is 280 K the yield stress is taken as 446.819 MPa.

Table 1: Value of the FeCrAl Yield Stress as a Function of Temperature

Temperature (K)Yield Stress (MPa)
290.735446.819
546.411313.964
640.150295.872
824.832225.901
1007.2467.237
1773.000.0

Example Input Syntax


[./fecral_plasticity]
  type = FeCrAlPlasticityUpdate
  block = '1 2 3 4'
  temperature = temp
  yield_stress = 1e-6 #should be ignored
  hardening_constant = 0.0
[../]
(test/tests/tensor_mechanics/fecral_plasticity/fecral_plasticity_rz_tm.i)

FeCrAlPlasticityUpdate must be run in conjunction with the inelastic strain return mapping stress calculator as shown below:


[./stress]
  type = ComputeMultipleInelasticStress
  tangent_operator = elastic
  inelastic_models = 'fecral_plasticity'
  block = '1 2 3 4'
[../]
(test/tests/tensor_mechanics/fecral_plasticity/fecral_plasticity_rz_tm.i)

Input Parameters

  • relative_tolerance1e-08Relative convergence tolerance for Newton iteration

    Default:1e-08

    C++ Type:double

    Description:Relative convergence tolerance for Newton iteration

  • hardening_functionTrue stress as a function of plastic strain

    C++ Type:FunctionName

    Description:True stress as a function of plastic strain

  • max_inelastic_increment0.0001The maximum inelastic strain increment allowed in a time step

    Default:0.0001

    C++ Type:double

    Description:The maximum inelastic strain increment allowed in a time step

  • temperatureCoupled Temperature

    C++ Type:std::vector

    Description:Coupled Temperature

  • base_nameOptional parameter that defines a prefix for all material properties related to this stress update model. This allows for multiple models of the same type to be used without naming conflicts.

    C++ Type:std::string

    Description:Optional parameter that defines a prefix for all material properties related to this stress update model. This allows for multiple models of the same type to be used without naming conflicts.

  • max_its30Maximum number of Newton iterations

    Default:30

    C++ Type:unsigned int

    Description:Maximum number of Newton iterations

  • yield_stress0The point at which plastic strain begins accumulating

    Default:0

    C++ Type:double

    Description:The point at which plastic strain begins accumulating

  • hardening_constant0Hardening slope

    Default:0

    C++ Type:double

    Description:Hardening slope

  • absolute_tolerance1e-11Absolute convergence tolerance for Newton iteration

    Default:1e-11

    C++ Type:double

    Description:Absolute convergence tolerance for Newton iteration

  • boundaryThe list of boundary IDs from the mesh where this boundary condition applies

    C++ Type:std::vector

    Description:The list of boundary IDs from the mesh where this boundary condition applies

  • acceptable_multiplier10Factor applied to relative and absolute tolerance for acceptable convergence if iterations are no longer making progress

    Default:10

    C++ Type:double

    Description:Factor applied to relative and absolute tolerance for acceptable convergence if iterations are no longer making progress

  • yield_stress_functionYield stress as a function of temperature

    C++ Type:FunctionName

    Description:Yield stress as a function of temperature

  • blockThe list of block ids (SubdomainID) that this object will be applied

    C++ Type:std::vector

    Description:The list of block ids (SubdomainID) that this object will be applied

Optional Parameters

  • effective_inelastic_strain_nameeffective_plastic_strainName of the material property that stores the effective inelastic strain

    Default:effective_plastic_strain

    C++ Type:std::string

    Description:Name of the material property that stores the effective inelastic strain

  • enableTrueSet the enabled status of the MooseObject.

    Default:True

    C++ Type:bool

    Description:Set the enabled status of the MooseObject.

  • use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

    Default:False

    C++ Type:bool

    Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

  • control_tagsAdds user-defined labels for accessing object parameters via control logic.

    C++ Type:std::vector

    Description:Adds user-defined labels for accessing object parameters via control logic.

  • seed0The seed for the master random number generator

    Default:0

    C++ Type:unsigned int

    Description:The seed for the master random number generator

  • implicitTrueDetermines whether this object is calculated using an implicit or explicit form

    Default:True

    C++ Type:bool

    Description:Determines whether this object is calculated using an implicit or explicit form

  • constant_onNONEWhen ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

    Default:NONE

    C++ Type:MooseEnum

    Description:When ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

Advanced Parameters

  • internal_solve_output_onon_errorWhen to output internal Newton solve information

    Default:on_error

    C++ Type:MooseEnum

    Description:When to output internal Newton solve information

  • internal_solve_full_iteration_historyFalseSet true to output full internal Newton iteration history at times determined by `internal_solve_output_on`. If false, only a summary is output.

    Default:False

    C++ Type:bool

    Description:Set true to output full internal Newton iteration history at times determined by `internal_solve_output_on`. If false, only a summary is output.

Debug Parameters

  • output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)

    C++ Type:std::vector

    Description:List of material properties, from this material, to output (outputs must also be defined to an output type)

  • outputsnone Vector of output names were you would like to restrict the output of variables(s) associated with this object

    Default:none

    C++ Type:std::vector

    Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object

Outputs Parameters

  • yield_stress_scale_factor1Scale factor to be applied to yield stress. Used for calibration and sensitivity studies

    Default:1

    C++ Type:double

    Description:Scale factor to be applied to yield stress. Used for calibration and sensitivity studies

Advanced: Scaling Factors Parameters

Input Files

References

  1. Y. Yamamoto, B.A. Pint, K.A. Terrani, K.G. Field, Y. Yang, and L.L. Snead. Development and property evaluation of nuclear grade wrought FeCrAl fuel cladding for light water reactors. Journal of Nuclear Materials, 467:703–716, 2015.[BibTeX]
  2. Y. Yano, T. Tanno, Y. Sekio, H. Oka, S. Ohtsuka, T. Uwaba, and T. Kaito. Tensile properties and hardness of two types of 11cr-ferritic/martensitic steel after aging up to 45,000 h. Nuclear Materials and Energy, 000:1–7, 2016.[BibTeX]