Struct TanakaModel 

pub struct TanakaModel {
    pub temps: TransformationTemperatures,
    pub a_m: f64,
    pub b_m: f64,
    pub a_a: f64,
    pub b_a: f64,
    pub h_max: f64,
    pub e_a: f64,
    pub e_m: f64,
    pub theta: f64,
}

Tanaka exponential kinetics model for SMA phase transformation.

The martensite fraction evolves as:

• Forward (A→M): ξ = 1 − exp(a_M (Ms − T) + b_M σ)
• Reverse (M→A): ξ = exp(a_A (As − T) + b_A σ)

where a_M, b_M, a_A, b_A are material constants derived from the transformation temperatures and Clausius-Clapeyron slope.

Fields

temps: TransformationTemperatures

Transformation temperatures.

a_m: f64

Exponential constant for martensitic transformation.

b_m: f64

Stress constant for martensitic transformation.

a_a: f64

Exponential constant for austenitic transformation.

b_a: f64

Stress constant for austenitic transformation.

h_max: f64

Maximum transformation strain.

e_a: f64

Austenite elastic modulus (Pa).

e_m: f64

Martensite elastic modulus (Pa).

theta: f64

Thermoelastic tensor Θ (Pa / K).

Implementations

impl TanakaModel

pub fn new( temps: TransformationTemperatures, cm: f64, ca: f64, h_max: f64, e_a: f64, e_m: f64, theta: f64, ) -> Self

Create a Tanaka model from transformation temperatures and material constants.

Parameters

• temps – transformation temperatures
• cm – Clausius-Clapeyron slope for martensite (Pa / K)
• ca – Clausius-Clapeyron slope for austenite (Pa / K)
• h_max – maximum transformation strain
• e_a – austenite modulus (Pa)
• e_m – martensite modulus (Pa)
• theta – thermoelastic tensor (Pa / K)

pub fn forward_fraction(&self, temp: f64, stress: f64) -> f64

Forward transformation (A → M): compute new ξ.

pub fn reverse_fraction(&self, temp: f64, stress: f64) -> f64

Reverse transformation (M → A): compute new ξ.

pub fn phase_fraction(&self, temp: f64, stress: f64) -> f64

Determine the phase fraction for a given (T, σ) state.

Selects forward or reverse based on where the temperature falls relative to the (stress-shifted) transformation temperatures.

pub fn effective_modulus(&self, xi: f64) -> f64

Effective elastic modulus at martensite fraction ξ.

pub fn stress_response( &self, strain: f64, temp: f64, xi: f64, temp_ref: f64, ) -> f64

Constitutive stress for given strain, temperature, and state.

Trait Implementations

impl Clone for TanakaModel

fn clone(&self) -> TanakaModel

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TanakaModel

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.