Thermal Spray Coatings in the Electrical and Electronic Industry
As metal spray or thermal spray coatings are typically pure metallics with no binders, they are very well suited to applications in the electrical and electronic industry.
How Thermal Spray Coatings Support Electrical Applications
Thermal spray coatings involve heating a material and spraying it onto a prepared surface to form a solid, bonded layer. The process allows specific surface properties to be added without affecting the core structure of the component.
This is particularly important in electrical and electronic applications, where parts can be sensitive to heat, pressure and contamination. Thermal spray processes transfer only limited heat to the substrate, making them well suited to delicate components.
The technology has become firmly established across the industry because it provides:
- Controlled electrical conductivity or insulation
- Protection against wear, corrosion and arcing
- Reliable bonding without damaging base materials
Capacitor End Spraying
One of the most established electrical applications for thermal spray coating is capacitor end spraying.
In thin film capacitors, the end faces are sprayed with zinc or tin/zinc alloys to electrically connect the internal foil layers. The coating also provides a strong surface for soldered wire connections.
Thermal spray coatings can be applied several hundred microns thick while transferring minimal heat, preventing damage to the plastic film inside the capacitor. The process is used on everything from small lighting capacitors, through to large power capacitors.
Conductive Coatings for Electrical Connections
Beyond capacitors, thermal spray coatings are widely used to create conductive surfaces for electrical connections – such as resin resistors, insulators and graphite heating rods.
Aluminium and aluminium bronze coatings are commonly applied to create reliable electrical contact surfaces that can handle mechanical load and electrical demand in service.
Electrical Insulation with Ceramic Coatings
Where insulation is required, thermal sprayed ceramic coatings provide an effective solution.
Ceramics such as alumina can be applied using plasma spray or powder flame spray processes to create a non-conductive layer. These coatings are often specified in high-temperature or high-voltage environments where stable electrical isolation is critical.
Electromagnetic Shielding
Thermal spray coatings are also used to create Faraday cages that protect equipment from electromagnetic emissions and interference.
This approach is commonly used for electrical switch boxes. However, a more specialised use of this technology is in radio rooms on mine-sweeping boats constructed from GRP (glass reinforced plastic).
Corrosion Protection for Electrical Equipment
Corrosion remains a major concern in the electrical industry, particularly for equipment installed outdoors or in harsh environments.
Thermal sprayed coatings of zinc, aluminium or their alloys are applied by flame spray or arc spray to protect steel switch boxes and transformer housings from long-term corrosion.
Working With Us
If you’re looking to improve conductivity, insulation or corrosion resistance in electrical or electronic components, thermal spray coatings could be the right solution.
Speak to the Metallisation team today to discuss your application, request technical guidance or get a quotation. A short conversation could save you time, cost and future headaches – and help your components perform exactly as they should.
Electrical Application Data Sheets
Earthing of resin insulators using the flamespray process
Reason for use: To produce a integral earth screen . The high voltage resin insulators required when using switchgear between 3.2 KV and 38KV can sometimes give rise to problems of air ionisation between metal components and the resin insulators.
Earthing of Resin Insulators Using Arcspray
Reason for use: To produce a integral earth screen. The high voltage resin insulators required when using switchgear between 3.2 KV and 38KV can sometimes give rise to problems of air ionisation between metal components and the resin insulators.
Metal spraying of capacitor ends
Reason for use: Electrical conductivity. The most common type of capacitor in use today is the foil-wound type. A thin film of metal, 1µm, is deposited on one side of a thin, 2.5 – 14µm, polymer film di-electric leaving one edge uncoated.