Electrical devices emit electrical or magnetic energy. But electrical noise, radio frequencies, and arc welders are the most common sources of electromagnetic interference (EMI). Sometimes, EMI negatively affects the performance of an electrical device or the transmission of signals. EMI shielding helps protect sensitive devices like mobile phones from electromagnetic interference. We’ll talk about six common materials used for EMI shielding in this brief article.
Aluminum, which is non-ferrous, is a cost-effective material that commonly shields electromagnetic interference. It’s the most preferred option due to its durability. Additionally, it’s flexible enough to allow molding to fit different shapes.
Mesh aluminum is the most widely used form, but you can also find an adhesive tape with bonded aluminum on one side.
Beryllium copper offers EMI shielding to protect cell phones from different frequency ranges. Many people prefer it due to its mechanical properties, including its high deflection range, high tensile strength, and long lifespan. Furthermore, it’s corrosion resistant and can thus withstand moisture and UV rays. Its mechanical spring properties make it ideal for use in high-motion applications, such as shielding an automatic door.
This is a more affordable option compared to beryllium copper. It’s ideal for various applications, especially those that require the reduction of a signal’s amplitude. Keep in mind that stainless steel doesn’t offer the electrical conductivity of the above common materials used for EMI shielding. However, it has a high heat tolerance and resists corrosion.
If you’re shielding frequencies in the kilohertz or lower gigahertz range, then pre-tinplated steel is an excellent option. Although it’s pretty expensive, this material has excellent corrosion resistance, and its pre-tinplated surface allows it to attach to a board through soldering.
Silicone for EMI shielding comes as a gasket. The idea is to fill the silicone gasket with a material like carbon to make it conductive. But you can also use silicone adhesive for EMI shielding. The adhesive option makes silicone a versatile EMI shielding material, as it can attach to various substrates.
Nickel often finds use as a shielding material when plated on other materials, such as plastic. When added to silicone gaskets, nickel is excellent electromagnetic shielding material. However, its effectiveness depends on some factors, such as the size of the shield and the shape.
Overall, all the above materials work for EMI shielding in different applications. If you’re looking to protect your mobile phone, frequencies, automated doors, or something else, then an expert might recommend any of the above materials.