Shrinkage prediction of MIM parts by Finite Element Simulation

The aim of this paper is to verify the reliability of numerical results obtained by using Mouldflow Plastic Insight (MPI) for prediction of metal part shrinkage. The approach implemented took advantage of the Finite Element (FE) analysis to simulate component fabrication and investigate the main causes of defects. Different FE meshes as well as shrinkage models were tested and evaluated. A Design of Experiments (DOEs) Technique was then used to plan the numerical simulation activity of the injection moulding phase and compare results with those obtained from the direct measurement of green parts. This research has confirmed that the choice of the correct shrinkage model was crucial to assess the influence of process parameter variation on part manufacturability, suggesting possible adjustments to improve part quality. Future researches will be addressed to the extension of analysis to large thin components and different classes of materials with the aim to improve the proposed approach. The originality of the work was related to the possibility of analysing component fabrication at the design stage and use the results in the manufacturing stage. In this way design, fabrication and process control were linked.