What is EMI shielding?

Electromagnetic interference shielding is the action of surrounding electronics and cables with conductive or magnetic materials to guard against incoming or outgoing emissions of electromagnetic radiation, that can interfere with their proper operation.

Electronics image (EMI shielding)

The shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields (EM shielding that blocks radio frequency electromagnetic radiation is also known as RF shielding). The amount of reduction depends heavily upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an electromagnetic field.

What is EMI shielding used for?

EMI shielding is done for several reasons, but the most common goal is preventing electromagnetic interference (EMI) from affecting sensitive electronics. Metallic mesh shields are often used to protect one component from affecting another inside a device.

Air gapped systems, usually used by military, government and financial institutions, can also benefit from EM shielding. Although physical isolation and a lack of external connectivity are often considered adequate to ensure the system’s security, several methods have been shown to successfully exploit the electromagnetic radiation that comes from different parts of the system.

How is EMI shielding done?

Various different materials and techniques are used for EM shielding. Wires may be surrounded by a metallic foil or shield to block EM emanations from the cased wires. Audio speakers often have inner metallic casing to block EMI produced by the drivers so they don’t affect TVs and other electronics. EMI filters are also found in electronic components, and more. Certain techniques are similar in concept to a Faraday cage, preventing signal corruption that would cause electronics to perform badly. Mesh can be used as total enclosure is not necessary if the openings are smaller than the electromagnetic waves that need to be blocked.

Typical materials used for electromagnetic shielding include sheet metal, metal screen, and metal foams. other shielding methods (especially used in electronic goods put in plastic enclosures) involve metallic inks that consist of a carrier material loaded with a suitable metal, typically copper or nickel, in the form of very small particulates. Copper is used for radio frequency (RF) shielding because it absorbs radio and magnetic waves.

Graphene EMI shielding

EMI shielding methods traditionally rely on metal, which adds weight and is expensive. A significant body of research demonstrates that carbon nanostructure-based nanocomposite materials can outperform conventional metal shielding due to their light weight, resistance to corrosion, flexibility, and processing advantages. On top of all these, graphene’s excellent conductivity makes it a perfect candidate for such applications.

Latest EMI Shielding news

The Polygraph project reports its results

PolyGraph project logoThe PolyGraph project, a 4-year development project with aims to develop new production techniques to deliver industrial scale quantities of graphene-reinforced thermosetting polymers, has published its results.

The POLYGRAPH (Up-Scaled Production of Graphene Reinforced Thermosetting Polymers for Composite, Coating and Adhesive Applications) project brought together 14 partners, including SMEs, companies, universities and a research center, and has reportedly led to the identification of the most suitable materials and production techniques for graphene-based coatings, adhesives and composites. Once the graphene market reaches maturity and material prices drop , these new products could appeal to a vast range of industries.

Graphene-coated smart contact lenses could protect eyes from EM radiation and dehydration

Researchers at Seoul National University, Graphene Square and Interojo have shown that graphene-coated contact lenses could protect eyes from electromagnetic radiation and dehydration and be used in various healthcare and wearable technologies.

The researchers began by synthesizing a graphene layer on a copper foil using CVD. They then transferred the carbon sheet onto the surface of a contact lens with the help of a polymer layer after etching the copper. "Thanks to its outstanding flexibility, graphene can be coated on the convex lens surface and conform to it," explains the team.

Graphene Batteries Market Report

Grafoid unveils a cost-effective graphene coating called GrafeneX

Grafoid logoGrafoid, a leading graphene R&D and investment company, announced its entry into the global industrial coatings market with the introduction of its patent pending GrafeneX graphene coatings technology. Grafoid describes the GrafeneX technologies as a cost-effective way of laying down graphene coatings on large surface areas.

GrafeneX is a novel technology that creates a platform for the deposition of graphene and chemically functionalized graphene coatings. This process provides Grafoid with the capability to apply its diverse graphene-based coatings to many different types of material substrates with controllable levels of surface coverage, thickness etc. to meet precise end user requirements.

Graphene 3D Lab introduces flexible conductive TPU filament

Graphene 3D Labs logoGraphene 3D Lab, a leader in the development, manufacturing and marketing of proprietary composites and coatings based on graphene and other advanced materials, recently announced the release of a new product. The Company will now offer a filament for 3D printing that is both highly electrically conductive and flexible.

G3L reports that the enhanced properties of this product make it ideal for applications involving flexible sensors, electromagnetic/radiofrequency shielding, flexible conductive traces and electrodes to be used in wearable electronics. This new material will be available for purchase in 1.75mm diameter 100 gram spools at the Company's on-line store, www.blackmagic3D.com, under the trade name of "Conductive Flexible TPU Filament".

GNext's graphene-based inks to soon enable recyclable EMI shielding sheets

Last week the Graphene-Info team visited the MWC - the world's largest mobile technologies conference held in Barcelona, which this year included a graphene pavilion, organized by the ICFO and the Graphene Flagship, Europe's $1 billion research project initiative.

One of the companies showcased in the pavilion was the Italy-based GNext, that demonstrated its graphene-based ink, used for rapid fabrication of electronic devices. GNext's ink can be printed using many common techniques on a wide range of substrates, including biopolymers such as PLA, and achieving a volume resistivity below 4 ohm/sq/mil.

Versarien - Think you know graphene? Think again!Versarien - Think you know graphene? Think again!