Joint design methodology based on the electromagnetic shielding effectiveness capabilities

The objective of this study is to provide guidelines for the best design of joints against electromagnetic interference (EMI). Six different joint geometries with different gap tolerances are evaluated and compared for their electromagnetic shielding characteristics. Based on the experimental study, a methodology for the best joint design has been developed. According to this methodology, addition of bends in the joint geometry has strong positive effect on the value of the shielding effectiveness (SE). It was observed that a sharp decrease on shielding effectiveness will occur for the larger gap size in the case of simple joints. Also, increasing the angle of cut, which increases the effective length of the joint, was also demonstrated to increase the shielding performance. Introduction of curved sections on the joint geometry also increased the shielding effectiveness which was depleted by increasing gap size.

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