MIM offers the same design freedom as plastic injection molding. Moreover, the more geometrically complex a part is, the more solid the rationale for manufacturing it via the MIM process. Parts may include cross holes, angle holes, internal threads, irregular shapes, splines, undercuts, side holes or grooves, complex contours, or cantilevers.
Parts that would usually be made by assembling multiple components can be designed as a single MIM part. Some parts that could not be fabricated via any other process can be made through MIM. Complexity that would be cost prohibitive to do via multiple machining operations or by casting and then finishing can be achieved cost effectively through MIM processing.
Medium to high volumes of components ranging from thousands to millions of parts annually are typically needed in order to be able to amortize costs associated with tooling and start-up engineering. The best economic advantages are achieved at the highest quantities due to the benefits of larger material purchases, multi-cavity tooling, and dedicated production units. Cell phones, eyeglass hinges, and orthodontic brackets are examples of well-designed components for MIM.
MIM fabrication is ideal where near-fully density, high-impact toughness, fracture toughness, and corrosion resistance are required. Additionally, MIM is compatible with most ferrous and non-ferrous alloy systems. If non-standard material properties are required, these can be developed with new alloy systems.
MIM is also appropriate for materials that are complex to machine, have multi-phase microstructures, or involve high work-hardening materials . It can deliver a high-quality surface finish (32 rms or better) and cleaner feature detail than investment casting.