Evaluation on Metal Injection Molding of Micro Parts

Metal Injection Molding (MIM) is a comparatively new method of manufacturing metal parts, combining injection molding process with flexible formability and powder metallurgy. Metal injection molding of small parts is named "μ-MIM" and is considered one of premising process to manufacture micro parts for various applications. In this study, micro-size specimens were molded by using a micro injection machine, and the inside mold pressure and density of green compact were investigated. Then the effect of molding condition on the density of green compacts was discussed. As the result, the inside mold pressure was observed higher at the near-gate-side than the far-gate-side at any molding conditions. The density of green compacts was not affected by the injection speed, but varied apparently depending on the material temperature. It was confirmed that the micro injection machine has some advantages for producing μ-MIM products.