Advantages and disadvantages of stamping, machining and MIM processing (2)

Metal powder injection molding technology (MIM) is a new powder metallurgy near net shape forming technology that combines modern plastic injection molding technology with traditional powder metallurgy technology. MIM products have high dimensional accuracy (±0.1%~±0.5%), good surface finish (roughness 1~5μm), and the output is very large. However, there are many MIM processes and there are certain technical barriers. Then why can't MIM make larger structural parts such as the middle frame/back cover of the mobile phone?

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First of all, the degreasing and sintering of MIM will reduce the size of the product. The larger the product size, the larger the deviation of the size and the less degreasing. Secondly, the MIM parts are mostly stainless steel. Although the stainless steel can be anode, the anode effect of aluminum is the best (mainly It is because the oxide layer of aluminum is composed of alumina, which forms an unconventional hexagonal tube structure, which produces a specular reflection effect and looks bright in color. Despite this, there are still companies trying to use the MIM process to make the middle/back cover of the mobile phone, which is a further excavation of the MIM process!