A method for modifying a cold-pressing precision forming die for a medicine-shaped cover part

Abstract

This invention proposes a method for correcting cold-pressing precision forming molds for shaped charge parts. It addresses the significant elastic deformation of the mold and springback of the blank during cold pressing, which are typically thin-walled, axisymmetric structures. This leads to a large discrepancy between the actual contour of the formed part after unloading and the target design, resulting in large machining allowances. The invention establishes a mold-blade elasto-plastic coupled finite element model to obtain the part contour and springback error after unloading. Combined with material experimental data, it performs multiple iterative compensations for springback and dimensional errors generated during cold pressing, continuously reducing springback error and thickness deviation until the accuracy requirements are met, obtaining the final corrected mold cavity curve. This method achieves precise approximation of the target contour, reduces the number of trial moldings, improves part dimensional accuracy and production efficiency, and provides an effective technical path for the efficient application of expensive and difficult-to-machine materials such as tantalum and tungsten.

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