EMI Shielding Explained – A Quick Guide

emi shielding
March 26, 2020

In today’s world, electronics are everywhere, from the phones in our pockets to radios in every vehicle to laptop computers that can go practically anywhere. Each of these electric devices creates electromagnetic waves, which are fine on their own, but problematic when the waves meet one another.

Electromagnetic interference, or EMI, can disrupt devices, equipment, and systems of all types, even critical electronics. EMI shielding protects against this interference using conductive metal materials that prevent electromagnetic waves from coming in or out of a device.

EMI shielding blocks the electromagnetic field, isolating electronics from their surroundings. When an electric field is applied to a conductor, like an EMI shield, it creates a current that displaces the charge inside of that conductor, which cancels out the electric field inside. EMI shielding manages the magnetic fields by reflecting radiation away from the surface of the conductor, keeping internal magnetic fields in and external magnetic fields out.

Where EMI Comes From

EMI is both man-made and naturally occurring. Solar magnetic storms, lighting, and the earth’s magnetic field flux are good examples of unavoidable EMI. Along with cell phones, radios, and computers, EMI also comes from everyday sources like power lines, electric motors, telecommunications transmissions, and digital signals. Electronics are ubiquitous these days, which means EMI interference needs to be considered for every item.

In a military and/or aerospace context, EMI can come from additional sources, including those specifically designed to disrupt or disable electronics. And high-altitude nuclear electromagnetic pulse, or HNEMP, is a concern with nuclear weapons testing. In fact, any kind of nuclear event is a concern within military applications, as even though a nuclear event is extreme, equipment needs to function regardless. EMP cannons are electromagnetic pulse weapons that also work to disable electronics without appropriate shielding.

Understanding these risks, it is clear to see why EMI shielding is so important. Any chance of unwanted EMI interference puts safety and reliability on the line, for people, for equipment, and for the citizens who depend on our aerospace and defense industries.

Dip Brazing and EMI Shielding

Dip brazing is one of the metal fabrication services we offer. We use a nonferrous metal filler between joints and then apply heat in a molten chemical or metal bath. The filler and joints are fused. When the product is ready, we heat treat it until it is hardened. This process results in metal joints that are leak-tight and EMI shielded. With its full coverage, dip brazing ensures improved conductivity as well, with filler metal that matches or surpasses the conductivity of the base metal.

Understanding the importance of EMI shielding in aerospace and defense applications, which are often mission-critical, we will work with you to understand the full scope of your project and your EMI shielding needs and ensure that we meet every requirement.

You can rest assured that our work is done to the highest standards, as we possess the certifications and qualifications that make us a preferred vendor for many other businesses in the industry. Our custom EMI shielded enclosures ensure your electronics are safe from interference, improving safety, reliability, and performance.

Our team is ready and willing to install EMI shielding as part of your enclosures in aerospace and military applications. Get in touch with us to learn more about our services. Contact New Age Metal Fabricating at 973.227.9107 or info@namf.com, or connect with New Age Precision Manufacturing at 631.471.4000 or info@napm.com. You can also send us a message online at your convenience.