Table 1.
NiTi material parameters which define its stress-strain curve. UMAT input material parameters for constitutive model implemented in Abaqus.
| Parameter | Description | Value |
|---|---|---|
| E A | Austenite elasticity modulus | 52650 MPa |
| ν A | Austenite Poisson's ratio | 0.33 |
| E M | Martensite elasticity modulus | 38250 MPa |
| ν M | Martensite Poisson's ratio | 0.33 |
| ε L | Maximum transformation strain | 8% |
| σ s AM | Start of transformation austenite-martensite stress | 320 MPa |
| σ f AM | End of transformation austenite-martensite stress | 360 MPa |
| σ s MA | Start of transformation martensite-austenite stress | 200 MPa |
| σ f MA | End of transformation martensite-austenite stress | 180 MPa |
| T 0 | Reference temperature | 22°C |
| C AM | ∂σ s,f AM/∂T | 6.7 MPa/°C |
| C MA | ∂σ s,f MA/∂T | 6.7 MPa/°C |