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.
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.
The latest graphene EMI shielding news:
Nanotech Energy has announced the debut of Nanotech EMI Armor Paint & Sheets, graphene powered coatings and films for electromagnetic interference (EMI) and radio frequency interference (RFI) shielding, as well as heat management.
The EMI Shielding line currently contains six products – all of which are said to be highly conductive and provide excellent external EMI/RFI protection while also preventing internal EMI/RFI leaks. The products can be sprayed, brushed, rolled or dip-coated onto various surfaces, such as glass, plastic and metal – depending on the specific product used.
Following a Global Business innovation Programme initiated in 2019, and a collaborative visit to the US, the UK established a new Graphene Innovation Group (UK-GIG) that puts together 15 specialists from UK companies that together share many years of experience in graphene and expertise across the entire value chain.
Scott Storey, a Business Innovation Advisor at Inventya and the lead coordinator at the UK-GIG, explains more about the group - "We can take an everyday industrial challenge, apply our combined graphene knowledge, engineer and manufacture an effective solution, and take that solution to national and international markets. UK-GIG is now an established cohort of 15 UK-based graphene companies, ranging from early stage through to established businesses. The UK-GIG companies are fully aware of the huge potential for graphene technology to improve materials or be used in novel ways across multiple sectors. They are seeking collaboration opportunities where they can combine their expertise to do what they do best - solve problems, design graphene applications, and help commercialize an increasingly exciting field. They aim to make the UK the best place on earth to be grafting in graphene!"
We have reached out to some of the GIG members, to find out how has graphene effected their business and products, and the effects of graphene on their materials or devices.
Sweden-based startup Graphmatech announced the launch of a new graphene-enhanced composite material. The new product, called Aros Create, is made of Nylon Aros Graphene pellets with a volume resistivity of less than 1 Ωcm while maintaining polymer lightweight, flexibility, processability, and recyclability.
The new composite may be used for extrusion, compression molding and injection molding and reportedly has unique electrical and tribological properties (low and stable coefficient of friction and high wear resistance). The potential applications are diverse, but the company's main focus is on electrical circuit components, LED, conductive coatings, additive manufacturing, EMI / RFI shielding, and charge dissipative coatings.
Graphene Flagship partners launch rocket to test the possibilities of printing graphene inks in space
Graphene Flagship partners, Université Libre de Bruxelles, University of Pisa and the University of Cambridge, in collaboration with the European Space Agency (ESA) and the Swedish Space Corporation (SSC), recently launched The Materials Science Experiment Rocket (MASER) into space. The objective is to test the printing of graphene patterns on silicon substrates in zero gravity conditions.
The experiment aims to test the possibilities of printing graphene inks in space. Studying the different self-assembly modes of graphene into functional patterns in zero-gravity will enable the fabrication of graphene electronic devices during long-term space missions, as well as help understand fundamental properties of graphene printing on Earth. This mission is also a first step towards the investigation of graphene for radiation shielding purposes, an essential requirement of manned space exploration.
Graphenest has launched two products, based on a proprietary graphene production method, now available to pre-order with a campaign price for a limited time.
The first product is HexaShield, a graphene-based paintable coating for RF electromagnetic interference (EMI) and radiation shielding. It reportedly provides drastic weight reduction, and reduced manufacturing cost as compared to metals, while achieving the required protection for the Gigahertz frequency range.