Understanding the benefits and drawbacks of Metal Injection Molding (MIM)
Metal Injection Molding (MIM)
Metal injection molding (MIM) is a manufacturing solution that uses the shaping advantage of injection molding technology. MIM, using fine (<20 um) metal powder, is capable of transforming complex concepts & designs into high precision, complex geometry net-shaped products from a wide range of materials such as carbon steels, low alloy steels, stainless steels, low expansion alloys (Kovar and Invar), tool steels, soft magnetic alloys, super alloys and non-ferrous materials like tungsten and copper.
MIM is ideal for mass-producing intricate engineering parts in medium to high volumes (over 10,000 parts annually). It is well suited for components weighing from 0.05 gm to 250 gm. Wall thickness is typically about 0.7 mm (0.3 in). However, AMT AMT pioneered the mass production of components with a localised wall thickness of 0.3mm (0.012in).
Tolerances are on the order of ±0.3 to 0.5%, albeit specific dimensions can be held as close as ±0.1%.
Eight reasons MIM may be suitable for you:
1. Suitable for components with highly complex geometries.
2. Wide selection of materials to meet specific product requirements. In addition, MIM can integrate two different types of material into a single part.
3. Provides the potential to integrate two or more separate parts into a singular, fully integrated part
4. Controlled porosity for lubrication & filtration applications
5. Good surface finishing (as-sintered around Ra 0.8um)
6. Potentially eliminate secondary processes such as machining
7. Flexible and low-cost mass production process
8. Low material wastage — 95% to 98% of raw material is packed and shipped out as a finished product
Considerations
While Metal Injection Molding is hailed as the go-to cost-effective manufacturing solution for mass production of complex metal components, it does not come without caveats. MIM is not the best fit solution in certain situations, including production requirements being less than 2,000 units/year, simple part design, or the investment cost in a mold or tooling does not meet economic justification.
AMT's MIM Expertise
By combining our MIM technology, material innovations and engineering expertise over the past 30 years, AMT can offer innovative solutions such as In-Coring?, bi-material integration, thin-wall capability, and more. Find out more about these innovative MIM applications here.
Although MIM technology is most ideally used for high-volume production, AMT has adapted to serve in high-mix, low-volume production. This innovative adaptation is because of our focus on serving the medical industry. For example, MIM technology is ideal for mass-producing components used in robotic surgical systems. These robotic surgical systems typically have end-effectors such as clamps, graspers, staplers, needle holders, etc., which are very complex geometries and shapes.