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.
Structural Backing Plate Deflection
Meaning
Mechanical bending of the primary support members in a casting machine occurs when the projected area of the part is subjected to high intensification pressure. Excessive structural backing plate deflection leads to a loss of parallelism between the die halves. The thickness and material of the plate determine its resistance to this bowing effect.
Over time this movement can fatigue the machine frame and lead to misalignment of the guide pins.
Rigidity Requirement
High tonnage machines must possess enough stiffness to counteract the forces that try to push the mold apart. If structural backing plate deflection is too great the mold will not seal correctly at the parting line. This requirement is especially strict for large structural castings like those found in modern electric vehicle chassis.
Flash Formation
Molten metal escapes from the cavity when the gap created by the bending exceeds the viscosity limits of the alloy. Reducing structural backing plate deflection is the primary way to minimize flash and secondary trimming costs. Consistent clamping pressure across the entire die face is needed for a clean casting.
Design Compensation
Engineers often increase the thickness of the support plates or add ribs to enhance the moment of inertia. Simulation of structural backing plate deflection helps in selecting the correct machine size for a given tool. Proper setup ensures that the internal pressure is balanced to avoid localized bending.