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Commercial electronic devices require shielding solutions that ensure electromagnetic compatibility (EMC) while accounting for effects of specific enclosure structural features such as seams, vents, and port dimensions. In practice, suitable EMC materials combine with the device operating characteristics to determine an overall shielding response. To optimally couple plastic design practices with EMC requirements, both polymer materials science and electrical engineering concepts, must be considered. Use of extrinsically conductive polymer (ECP) formulations for electronic applications has advantages in that they can be directly molded to a desired shape and serve to provide the necessary shielding while also meeting mechanical integrity requirements. Shielding and mechanical performance can be varied via filler loading or altered through wall thickness changes to satisfy demands associated with a particular device. Injection-moldable ECP polycarbonate-based formulations can attain average shielding effectiveness (SE) levels of 50-60 dB through 2 GHz at 2-mm thickness as measured using ASTM D 4935 procedures. These values vary with thickness, and SE improvements of 10-20 dB are observed when increasing from 1 to 2 mm. Additionally, resultant mechanical properties of shielding composites are strong functions of overall fiber content. These interrelated material and shielding characteristics, which form the basis for filled conductive polymer use within practical enclosure shielding designs, are described.

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Modification of the Al2O3–Al system's chemistry via the addition of B4C is described and is shown to result in fully dense structures via wetting techniques at high temperatures, without the need for pressure‐assisted infiltration. The relationships between the surface area of boron carbide and alumina powders, the effectiveness of infiltration, the material chemistry following infiltration, and the resulting mechanical properties of Al2O3–B4C–Al composites are evaluated. Additional approaches, including the incorporation of aluminum metal powder as an additional wetting agent before infiltration, are described in conjunction with a variation of both the surface areas and the volumetric ratios of inert Al2O3 to reactive B4C phases. These methods can provide the means to achieve low‐cost metal matrix composites in both vacuum and argon infiltration environments, and represent an approach that enables the generation of articles with complex geometries, requiring minimal secondary finishing treatment.