Currently, the most used options for EMI shielding are metal covers, metalized plastic covers, standard plastic with metal sheet/foil, conductive plastic covers and carbon fiber composite structures. Although prominent, they have drawbacks that can lead to reliability risks, higher weight or assembly costs.

For instance if the shield is not reliable, EMI can cause system-malfunction, and even failure. Consequence of system interference can be dangerous—there have been reports of airbags deploying, triggered by emergency service vehicle RF transmissions and engine management, and cruise control systems demanding ‘full throttle’ when subjected to EMI. 

Balancing conductivity and good mechanics

To ensure reliability during vehicle operation, the proper shielding of emitters is necessary. It has been found that 40-50dB shielding is sufficient for almost all EMI shielding applications, and that performance differentiation is achieved via sophisticated interface science polymer/fillers.

When designing with conductive material solutions, there are several advantages:

• Design freedom – sleek design with high flexibility, improving overall efficacy of the module, EMI shielding and thermal conduction 
• Lower weight – up to 50% weight reduction vs. Aluminum
  
• High productivity – lower energy consumption and longer tool life as compared to Aluminum
  
• No secondary finishing processes (drilling, sanding, painting, etc.)
  
• Inherent corrosion/oxidation resistance
  
• Increased reliability (no delamination of paints or coatings)
  
• Total cost reduction vs. machined metal components
  
  

DSM’s Xytron^TM PPS offers best in class shielding carbon fibre (CF) composites with the highest shielding levels, thermal conductivity and good mechanics. Composites reduce wall thicknesses by four times and increase the conductivity to metal levels.

At DSM, we support our customers and help them win in powertrain electrification by offering an advanced material solution, along with design support for metal replacement.

To learn more contact us or visit Plastics Finder.