Coefficient of Thermal Softening
The yield stress Y of a material decreases linearly with temperature. This relation can be represented by the equation:
Y=Y0*(1–CTS*(Tmodel–Tref))
where
Y0 is the yield stress at the reference temperature
Tmodel is the temperature of the model
Tref is the reference temperature
CTS is the coefficient of thermal softening which is a constant for a material
The coefficient of thermal softening is a parameter that is common to all the hardening laws. You must specify this value regardless of whether you define the elastoplastic material using stress-strain data or by specifying material constants for a selected isotropic hardening law. The default value is zero and it has units of per unit temperature.
When running an analysis, if CTS*(Tmodel-Tref) is greater than 1 the yield stress becomes negative. This indicates that the value you have specified for CTS is too high.
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