Filling of Microarray Fabricated by Micro Powder Injection Molding

Abstract:

Flow analysis during injection molding is crucial for dimensional control in micro powder injection molding. Numerical simulation of injection molding of ZrO₂ microarray based on in-house feedstock was conducted. A powder-binder two fluid model was developed to analyze temperature, viscosity and powder volume fraction of the feedstock for micro pillars of different dimensions with diameters of 0.2, 0.5 and 1 mm, respectively. In general the binder temperature decreased with size reduction of the micro cavity caved on the silicon wafer and increased with mold temperature. The micro pillars of φ0.2 mm exhibited the highest viscosity, which indicated difficulty for filling during injection molding. An increase in mold temperature facilitated the decrease of the feedstock viscosity, which improved the filling of the micro cavities. Powder-binder segregation became evident as the size of the micro cavities reduced to 0.2 mm.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 1171-1176
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.1171
• Online since: June 2017
• Authors: Lin Liu*, M.X. Qi, Z.Q. Xie, Z.Y. He, F. Ming
• Keywords: Micro Powder Injection Molding, Microarray, Simulation, Submicron Zirconia Powder

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