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

Graphematech and Add North 3D develop novel graphene-enhanced 3D printing filaments

A collaboration between two innovative material technology startups Graphmatech and Add North 3D (a Swedish 3D materials developer specialized in FDM materials) has developed novel conductive Aros Graphene-based filaments for 3D printing. This may open up many new different 3D-printing applications such as thermal management components, circuit boards and efficient electromagnetic and radio frequency shielding.

The recently developed 3D-printing technology based on Graphematech's Aros Graphene may grant the ability to control the exact level of conductivity of the filament. The new filaments will now be optimized and go through beta testing with a reference group before it is expected to reach the market in 6-12 month.

Talga Resources reports breakthrough on its graphene-infused concrete project

Australia-based advanced materials company Talga Resources has reported high levels of electrical conductivity in concrete by using an additive developed from the Company’s graphene-graphite research and development laboratory in the UK.

Talga reports advancements of graphene-enhanced concrete project image(L) Talga concrete sample after melting 5cm depth of ice from 9v power. (R) Conceptual underfloor heating/road application.

The reported breakthrough offers substantial potential in existing and emerging industrial applications, particularly as concrete is the world’s largest construction material by volume. Talga shared information gathered from tests that show that the graphene-enhanced concrete is highly electrically conductive - attaining 0.05 ohm.cm volume resistivity.

The Graphene Handbook

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.

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.

XFNANO: Graphene and graphene-like materials since 2009XFNANO: Graphene and graphene-like materials since 2009