Linear kinematic hardening

Overview

This object implements simple linear kinematic hardening. The backstress is defined as

$\mathbf{X} = -H \bm{\chi}.$

The model requires a length 6 history variable ( $\bm{\chi}$ ) and maps to a length 6 backstress ( $\mathbf{X}$ ).

Warning

All of the NEML yield surfaces assume the opposite of the standard sign convention for isotropic and kinematic hardening. The hardening model is expected to return a negative value of the isotropic hardening stress and a negative value of the backstress.

Parameters

Parameter	Object type	Description	Default
`H`	`neml::Interpolate`	Linear hardening constant	No

Class description

class LinearKinematicHardeningRule : public neml::KinematicHardeningRule 

Simple linear kinematic hardening.

Public Functions

LinearKinematicHardeningRule(ParameterSet &params): Parameter is the linear hardening coefficient.

virtual void q(const double *const alpha, double T, double *const qv) const: q = -H * alpha[:6]

virtual void dq_da(const double *const alpha, double T, double *const dqv) const: Derivative of the map.

double H(double T) const: Getter for the hardening coefficieint.

Public Static Functions

static std::string type(): String type for the object system.

static std::unique_ptr<NEMLObject> initialize(ParameterSet &params): Initialize from a parameter set.

static ParameterSet parameters(): Default parameters.