Impact of Electromagnetic Pulse (EMP) on Conductive Rubber Gasket Electromagnetic Shielding Performance

ABSTRACT This study investigates the impact of EMP on the electromagnetic shielding performance of conductive rubber gaskets by simulating EMP exposure through ringing pulse injection. After the injection of ringing pulse with peak surface current range from 0.50 × 10 5 to 4.53 × 10 5 A/m, both the volume resistivity and transfer impedance of the conductive rubber gasket decrease, indicating improved electromagnetic shielding performance. The improvement in electromagnetic shielding performance reaches its maximum under the condition of 3.53 × 10 5 A/m. We attribute this phenomenon to the combined action of two mechanisms. When the current is less than 3.53 × 10 5 A/m, EMP injection induces the formation of ablation zones around conductive particles. These ablation zones exhibit higher elastic modulus and provide greater movement space for conductive particles, thereby improving the electromagnetic shielding performance; however, as the current density increases to 4.53 × 10 5 A/m, the expansion of the ablation zone within the conductive rubber matrix leads to the formation of “hollow zones” in a specific region. The formation of hollow zones partially counteracts the beneficial effects of EMP injection on the electromagnetic properties, resulting in a reversal in the trend of shielding enhancement.