MIM is a manufacturing process which is able to deliver near net-shape metal components by compressing metal powder in a special sintering process.
MIM offers significant cost savings compared to the use of conventional machining or electrical discharge machining. Used especially in the medical and automotive sectors, it can offer significant savings to customers.
With minimal raw material waste, as well as reduced cycle times, MIM can reduce costs by more than 50%,it is currently seen as a strong and reliable solution for overcoming several important economic challenges. MIM offers high volume manufacturing of tightly-toleranced small metal components. Automotive and medical applications are two of the main sectors driving the increase in the demand for MIM components.
By using this MIM process, it is possible to combine several separate parts into one. This significantly reduces development time and effort and improves supplier tracking.
Using MIM it is possible to produce complex, three dimensional shapes that are difficult or near impossible to manufacture using conventional fabrication technologies. MIM provides for complex shapes in medium to high volume manufacturing process.
Metal Injection Moulding is an innovative manufacturing process in which fine metal powder mixed with a special thermoplastic binder is injected into a mould to form the required shape. The MIM component is ejected from the mould, the binder is then removed and then the component is sintered, to produce a high-density metal component. Whilst the design principles are broadly similar to those used for plastic injection mouldings and pressure die-castings, the properties that can achieved using the MIM process are far superior. MIM is ideal for high volume, small, complex geometry, thin wall metal components. Being a net-shape process, MIM is most competitive where costly machining operations can be avoided and where the number of parts required is sufficiently high to justify the cost of the mould.
As with other primary metal manufacturing processes, a number of other secondary operations could be carried out to MIM components to add features or enhance properties.
Metal Injection Moulding applies the principals of injection moulding to the well-established technology of powder metallurgy and to produce complex components in steels and high strength materials with tight tolerances, fine surface finish and finely reproduced detail.
Complex Shapes, combine a number of simpler components together into a single component
Good Surface finish typically around 1.6µm.
Improved Mechanical Properties, with densities approaching that of wrought materials
High Production rates
Small Components Typically less than 0.1kg
Thin components typically 6mm max
Tooling costs and lead time.
Characteristics | MIM | P/M | Die Casting | Investment Casting | Machining |
Complexity | High | Low | High | Fair | High |
Min. Wall Thickness | 0.5 mm | 1mm | 0.8mm | 2mm | 0.5 mm |
Surface Roughness 1.6 μ m Ra | Fine | Coarse | Medium | Medium 5 μm Ra | Fine |
Mechanical Properties | Good | Fair | Medium | Fair | Good |
Varieties of Materials | Many | Many | Few | Average | Many |
Density | 95 - 99% | < 95% | 99~100% | 99~100% | 99~100% |
Accuracy | High | High | Medium | Medium | High |
Plating Quality | Good | Poor | Medium | Good | Good |
Productivity | High | High | High | Medium | Low |
Cost | Medium | Low | Low | Medium | High |
Dimensions in mm | Suggested Tolerance |
25.0 | + / - 0.100 |
12.0 | + / - 0.050 |
6.0 | + / - 0.040 |
3.0 | + / - 0.030 |
1.0 | + / - 0.030 |