Design Guide

Metal Injection Molding (MIM) offers great freedom in component design, making this process unique for mass production of metal components. Metal powder injection molding can be used to produce extremely complex components in one go, turning two parts into one; reducing production processes and saving time in production.

Complex

MIM offers the same design freedom as plastic injection molding, providing nearly unlimited shape capabilities. Because MIM is a molding process, additional product features do not increase cost, which makes MIM ideal for combining individual parts into multifunctional products. The design rules for MIM are very close to those for plastic injection molding, so it can be easily adapted to almost any product.

Accuracy

The injection molding machine A general guideline for MIM net-shape feature accuracy is ± 0.5% of dimension. Some features can achieve net-shape accuracy of ± 0.3%. As with any technology, higher accuracy means higher cost, so loosening tolerances whenever possible is encouraged. Tolerances that cannot be met with MIM alone can be achieved with a variety of finishing processes.

Weight and Size

MIM is best suited for parts weighing less than 100 grams, with the most economical application being parts weighing less than 50 grams. However, parts weighing up to 250 grams have been machined. Raw material is a key cost driver for the MIM process. MIM promotes creative methods to reduce part weight as much as possible. Similar to plastics, coring and ribs can be used to reduce weight without compromising the integrity of the product. MIM excels at producing extremely small and micro parts, which may weigh less than 0.1 grams. Weight is not a limiting factor, and products over 250 mm in length can be machined..

Section Thickness

The injection molding machine Wall sections less than 6 mm are best suited for the MIM process. Thicker sections can be achieved, but this will also increase cost due to longer processing time and additional material. Alternatively, very thin sections less than 0.5 mm can be achieved with MIM, but are highly design dependent.

Volume

MIM is a highly scalable process. Volumes ranging from a few thousand parts to millions of parts per year can be economically achieved. Similar to casting or plastics, the MIM process requires tooling and engineering investments, which often drives the decision process for lower volume products.

Materials

The injection molding machine MIM can process a wide range of materials, including ferroalloys, nickel-cobalt-based superalloys, titanium alloys, refractories, cemented carbides, technical ceramics and metal matrix composites. While non-ferrous alloys such as aluminum and copper alloys are technically processable, it is more economical to process them by other means such as die casting or machining.