EMC Question of the Week: April 29, 2019
Materials such as plastics with embedded carbon nanofibers can make better shielded enclosures than metallic enclosures because they
- absorb more power
- reflect more power
- transmit more power
- have no seams
Answer
The correct answer is "a." Although they may have a lower plane wave shielding effectiveness, plastics with embedded carbon nanofibers can make excellent shielded enclosures that outperform metal enclosures. Metal enclosures reflect almost all of the incident power back into the enclosure. This generally makes the fields in the enclosure stronger, which enhances radiation from seams and apertures. A shielding material that absorbs more of the incident power can sometimes make a more effective shielded enclosure by lowering the peak fields inside the enclosure. This is particularly true for products that do not have a significant volume of internal objects or materials that reduce the Q-factor at enclosure resonances.
Have a comment or question regarding this solution? We'd like to hear from you. Email us at