DESIGN GUIDELINES

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oday, MIM is serving critical performance applications in a wide range of industries and products including, automotive, aerospace, consumer electronics, dental implants and instruments, electronic and fiber optic connectors, hermetic packages, surgical instruments and implants, power and hand tools, hardware and sporting gear.

Products most appropriate for MIM usually have the following characteristics.


Complexity:

MIM allows the same design freedom as plastic injection molding which gives almost limitless shape capability. Because MIM is a molding process, additional product features do not add cost, which makes MIM ideal for combining individual parts into multi-functional products. Design rules for MIM are very close to that of plastic injection molding thereby making it easy to adapt to almost any product.

Precision:

The general guideline for MIM precision of net shape features is ± 0.5% of the dimension. Certain features can be made net shape to ± 0.3%. As with any technology, higher precision equates to higher cost so relaxation of tolerances is encouraged wherever possible. Tolerances that are not capable of being met by MIM alone can be achieved through various finishing processes.

Weight and Size:

MIM is best suited for parts weighing less than 100 grams with the most economical applications being less than 50 grams. However, part weights of up to 250 grams have been processed. Raw material is a key cost driver for the MIM process. MIM promotes creative ways to reduce part weight wherever possible. Similar to plastics, coring and ribs can be used to reduce weight without compromising product integrity. MIM excels at extremely small and micro-sized parts with weights of less than 0.1 gram being possible. Weight not being a limiting factor, product lengths in excess of 250 mm can be processed.

Section Thickness:

Wall sections of less than 6 mm are most appropriate for the MIM process. While thicker sections are possible, this also drives up cost due to longer processing times and additional material. Alternatively, very thin sections of less than 0.5 mm are possible for MIM to achieve but are highly design dependent.

Production Volumes: MIM is a highly scalable process. Low volume of several thousand parts annually up to millions of parts can be economically achieved. A tooling and engineering investment is necessary for the MIM process similar to casting or plastics, which will normally drive the decision process for low volume products.

Materials: MIM can process a wide array of materials including Ferrous alloys, Nickel and Cobalt base Super alloys, Titanium alloys, Refractory materials, Cemented carbides, Technical ceramics and Metal matrix composites.While non-ferrous alloys such as Aluminum and Copper alloys are technically possible but they are more economically processed by other means such as die casting or machining.Please check our materials section for more information.

Applications Assistance: Indo-MIM provides comprehensive assistance to achieve the most value from the MIM process. We help with migration of existing products in both design conversions and materials selection as well as a full range of product development services including industrial product design, FEA, rapid prototyping and laser scanning.

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