Coupled Thermomechanical Strain Life FEA for Large Format Gigacast Tray Molds
Coupled thermomechanical strain-life FEA predicts thermal checking and insert fatigue life in gigacast tray molds using non-linear elastoplastic plasticity models.
Non Linear Kinematic Hardening
Meaning
Advanced plasticity modeling accounts for the shifting of the elastic limit when a material undergoes repeated cycles of tension and compression. Utilizing non linear kinematic hardening allows for a more accurate prediction of residual stresses in components subjected to fluctuating thermal loads. Unlike simpler models this approach captures the path dependent nature of plastic deformation.
Bauschinger Effect
Stress reversal shows that the yield strength in compression decreases after the material has been plastically strained in tension. The non linear kinematic hardening law represents this behavior by moving the center of the yield surface in stress space. This is helpful for assessing parts that undergo complex loading histories during assembly and operation.
Cyclic Fatigue
Materials that experience plastic strain in every cycle eventually fail through crack initiation. Prediction of this failure requires non linear kinematic hardening parameters to model the accumulation of damage over thousands of cycles. Accurate simulation prevents the overestimation of the fatigue life of structural battery frames.
Model Application
Finite element software uses these equations to simulate the manufacturing processes and subsequent operational stresses. Calibrating the non linear kinematic hardening variables requires experimental data from stabilized cyclic tests. Engineers use these results to refine the geometry of parts to ensure they stay within the elastic range as much as possible.