Composite material to protect security devices against electromagnetic interference

Electromagnetic interference has become a major problem for the design of electronic and electric devices, especially security device, where the great emphasis is placed on the reliability. Currently, the boxes of security device are mostly produced using plastic material. However, this material is not able to protect devices against electromagnetic interference, and this leads to efforts to find new ways and materials suitable for protecting the devices. In addition to the electromagnetic immunity requirements, the weight and ductility of the material must take into account. One of the variant how to protect equipment describes this paper focusing on the combination of a commercially available product and nano-layers of gold. The commercial product consists of rubber and ferrite. The advantage of this variant is material flexibility and relatively satisfying resistance to electromagnetic interference. The combining different types of materials can increase the electromagnetic immunity; however, it can lead to an increase in the weight of the final product or a worsening of the ability to model the material as needed. The fundamental structural element of the design was a commercial material combining rubber and ferrite, the structure of which the layer of gold was applied which is expensive but electrically conductive and presents an interesting aesthetic variation. The composite material was tested in the frequency range from 10 MHz up to 2 GHz which is the range corresponding to the European standards. The purpose of the paper is to determine the effect of the composite materials regarding electromagnetic immunity.