To overcome the lack of micro manufacturing processes suitable for medium and large scale production as well as to process high resistive materials a special variant of micro injection molding is currently under development: micro powder injection molding (MicroPIM), which already enables the manufacturing of finest detailed components with structure sizes down to a few ten micrometer. In order to expand the scope of application of MicroPIM, tests are being conducted with pure tungsten powders or tungsten alloy powders. As further improvement, micro twocomponent injection molding allows, for example, the fabrication of micro components consisting of two ceramic materials with different physical properties.

Self-heating nanocomposites with a positive temperature coefficient (PTC) provide outstanding potential for a broad range of engineering applications in automobile, spacecraft, or smart building. Therefore, extensive studies have been carried out to understand thermo-electrical behavior. However, some controversies remain, especially on the material composition, to clarify influencing factors on the PTC performance. In this study, the thermo-electrical behaviors of injection molded carbon black (CB)/polyamide (PA) nanocomposites have been investigated. Three types of CB with well-defined specific surface area and polyamides with high and low crystallinity were selected to provide a guideline for self-heating devices including PTC-Effects. Significantly reduced specific resistances up to 2.7 Ω·cm were achieved by incorporating CB with a high specific surface area into a highly crystalline PA. Noticeable PTC-Effects of ~53% and average surface temperatures up to 147 °C have been observed due to self-heating, which confirms a promising material performance as a heating device.

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