RFI and EMI – Shielding and Absorbing Materials

1. What is EMI/RFI Shielding?

EMI/RFI shielding reduces the likelihood of electronic failures by blocking unwanted external electromagnetic waves or preventing internal electromagnetic waves from radiating and interfering with other circuits or devices.

 

2. What are RFI and EMI Shielding Materials?

RFI and EMI shielding materials are designed to absorb, reflect, or conduct electronic noise away from or around sensitive equipment and circuits. Common shielding materials include aluminum, copper, tin, epoxy and ferrite powders, gold fabric, nickel, acrylic, and various polyester fibers.

 

3. What are the Working Principles of RFI and EMI Absorbing Materials?

RFI (radio frequency interference) absorbers absorb electromagnetic radiation, typically in the frequency range of 10 MHz to 10 GHz, and convert it into small amounts of heat. These materials are typically conductive or magnetic, such as metal foam, metal mesh, and ferrite sheets.

 

EMI (electromagnetic interference) absorbers absorb electromagnetic radiation, typically in the frequency range of 1 kHz to 10 GHz, and convert it into small amounts of heat. These materials are typically conductive or magnetic, such as metal foam, metal mesh, and ferrite sheets. They work by dissipating the energy of electromagnetic waves into the material through absorption and reflection, thereby reducing the amount of energy reaching the target.

 

4. What are the Types of Absorbing Materials?

Acoustic Foam

Fibrous Materials

Mineral Wool

Cellulose

Polyurethane Foam

Cork

Polyester Fiber

Melamine Foam

Wool

Rubber Foam