Comparison of Numerical Methods for Geometric Warpage Compensation

Abstract

In injection molding processes, shrinkage and warpage often cause deviations in the shape of produced parts compared to the cavity shape. These deviations arise due to uneven cooling and internal stresses within the part. One approach to mitigate these effects is by adjusting the cavity shape to anticipate the deformation. This can be achieved by simulating the expected deformation using suitable models, which then inform the optimization of the cavity shape for injection molded parts with minimal deformation. \\In this study, we evaluate various numerical algorithms from existing literature to identify the optimal cavity shape. Each method is briefly outlined regarding how it adapts the geometry, and we discuss their respective strengths and weaknesses for different scenarios. We conduct comparisons using 3D geometries of varying complexity. Our findings demonstrate that, for geometric warpage compensation, the node-based reverse geometry method yields the least warpage and is computationally cost-effective. Furthermore, it is straightforward to implement and consistently performs well across different geometries.