Salehi, M., Neo, D. W. K., Rudel, V., Stautner, M., Ganser, P., Zhang, S. X., Seet, H. L., & Nai, M. L. S. (2024). Digital manufacturing of personalized magnesium implants through binder jet additive manufacturing and automated post machining. Journal of Magnesium and Alloys. https://doi.org/10.1016/j.jma.2024.07.027
Abstract:
While magnesium (Mg) is a promising material for personalized temporary implants, the lack of a digital manufacturing solution for Mg implants impedes its potential progress. This study introduces a hybrid manufacturing process that integrates binder jet additive manufacturing with automated dry post-machining to enable end-to-end digital manufacturing of personalized Mg implants. Spherical cap-shaped Mg implants were additively manufactured through binder jetting. These implants were placed on graphite flakes during sintering as a potential non-reactive support material, allowing unrestricted shrinkage of 15.2 % to a relative density of 87 %. Microstructural and dimensional analysis revealed consistent interconnected porous microstructures with a shrinkage distortion within ± 0.2 mm of the original digital drawing. High-speed dry milling of the sintered samples, assessed via an orthogonal cutting test, identified the optimized cutting parameters. A three-step machining process for automated 5-axis machining, along with clamping strategies, referencing, and an adaptive plug-in, were successfully implemented. The automated dry machining on binder-jet printed Mg implants resulted in an average roughness of < 1.3 µm with no defects. In summary, this work introduces a robust digital manufacturing solution to advance the transformative landscape of Mg implants and scaffolds.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This research is supported by the first Singapore-Germany academic-industry (2+2) international collaboration grant