How does zinc die casting improve EMI shielding in enclosures?
How Does Zinc Die Casting Improve EMI Shielding in Enclosures?
Importance of EMI Shielding in Modern Electronic Enclosures
EMI (Electromagnetic Interference) can disrupt the performance of electronic devices by allowing external signals to interfere with internal circuits or allowing emissions from the device to affect other equipment. Effective EMI shielding is essential for compliance with regulatory standards (such as FCC, CE) and for maintaining signal integrity in automotive, telecom, medical, and consumer electronics. Die cast enclosures made from zinc alloys provide a reliable and cost-effective solution.
Why Zinc Die Casting Is Effective for EMI Shielding
Zinc die casting is inherently suitable for EMI shielding due to its material properties and casting capabilities:
High electrical conductivity: Zamak alloys, especially Zamak 3, offer conductivity around 27% IACS, enabling excellent electromagnetic attenuation.
Complete 360° coverage: Die cast housings form seamless enclosures with minimal joints, eliminating EMI leakage paths.
Good thermal conductivity: Assists in managing heat while simultaneously blocking radiated signals.
Precision casting: Allows for integrated grounding features, boss structures, and internal partitions that enhance shielding effectiveness.
Advantages Over Other Materials
Compared to plastic: Zinc eliminates the need for additional conductive coatings or inserts.
Compared to aluminum: Zinc allows thinner walls and tighter tolerances with better surface quality, especially for small enclosures or snap-fit assemblies.
Compared to stamped metal: Die casting enables complex, multi-directional geometries that are difficult or costly to form from sheet stock.
Design Features That Enhance Shielding
Neway supports enclosure designs optimized for EMI control through:
Interlocking covers with tight tool and die tolerances
Integrated gasket grooves for conductive seals
Cast-in bosses for direct PCB grounding
Smooth external surfaces ideal for electroplating or powder coating when needed
Zinc die casting also supports secondary CNC machining to ensure precise interface flatness and EMI gasket contact points.
Surface Treatments for EMI Shielded Zinc Enclosures
Zamak parts can be enhanced with:
Nickel or tin plating for increased surface conductivity
Chromate conversion coatings for corrosion resistance without compromising conductivity
Black chrome or decorative finishes that maintain EMI integrity while matching industrial design
Neway’s Capabilities for EMI-Resistant Zinc Enclosures
Neway provides end-to-end production of zinc-based EMI enclosures through:
Precision zinc die casting with Zamak 3 and 5 alloys
Post-processing including plating and coating for shielding enhancement
Dimensional control and sealing via CNC machining
Assembly and gasket integration for finished electronic housing systems
