Coating Solution for the Electrical Insulation Industry
Coatings for Electrical Insulation
Since the mid-90s, Rilsan® fine powder coatings, specifically the Rilsan® polyamide 11 from Arkema, have been the go-to coating product for electrical insulating applications. Originally used for electrical cabinets, these biobased coatings are now used in many different applications across industries. The Rilsan® polyamide 11 offers great protection from UV and high voltages, provides excellent flexibility, and protects from corrosion and abrasions.
Importance of Dielectric Insulation
Dielectric insulation plays a crucial role in preventing electrical failures and provides reliable safeguards for equipment. A material's dielectric strength quantifies its ability to withstand electric breakdown when an electrical field is applied and the electrons within the insulating material polarize, resulting in a weaker outgoing electrical field, as shown in the diagram below.
The ability to polarize an electrical field can be due to many factors, including the shape of the electrode, the waveform and rate of change in voltage, and the length of time a voltage stress can be maintained. The reliance on electricity that exists today with all its technology puts more importance on a material's ability to withstand electrical fields before breaking down.
Rilsan® Fine Powder Coatings Properties
With the importance of insulating electrical currents, coating materials like Rilsan® fine powder coatings can aid in the dielectric properties of certain materials. The dielectric properties of Rilsan® powder coatings can range from 5 kV per millimeter up to 65 kV per millimeter. The dielectric strength of Rilsan® coatings can be easily adjusted based on the thickness of the coating, as shown in the graph below.
Since polyamide 11 is a thermoplastic material, this gives Rilsan® fine powder coatings more adjustability during processing, allowing for more variety in coating thickness and dielectric strength. For EV battery components, insulation level requirements are around 5 kV/mm, while other applications can require a coating thickness of up to 1.25 mm, resulting in a dielectric strength of over 20 kV/mm.
Why Use Rilsan® Fine Powder Coatings?
Mechanical Durability
Rilsan® coatings have significantly better wear and impact resistance than other materials like epoxies.
Thermal Stability
At higher dielectric resistance, a lower thickness of coating is needed, allowing for more efficient thermal dissipation.
Superior Weatherability
With superior thermal stability, this powder coating can withstand intense UV exposure and extreme thermal cycling.
Chemical Resistance
These coatings have shown no adverse affect after long-term exposure to solutions like sodium hydroxide and sulfuric acid.
Excellent Flexibility
These coatings pass ISO 6860 (bend test for paints and coatings) at over 250 μm.
Efficient Processing
Rilsan® powder coatings can lead to a reduction in cost through it's efficiency and recyclability.
Compared to thermoset materials like epoxy, thermoplastics do not need to undergo a chemical reaction to form a solid coating. Thermoplastic coatings can be processed more easily without the need for precise cure time and temperature often associated with epoxies and other thermoset materials.
Additionally, parts can be formed and machined even after the coating is applied. Due to the material's flexibility, parts can be bent or cut, creating metal contact points where needed. Rilsan® fine powder coatings are also cost-efficient since less coating can be used to achieve similar dielectric strength, and a lower coating density equates to more parts per pound.
Multi-industrial Coating
Due to its flexibility, Rilsan® powder coatings can be applied to a variety of substrates, such as steel, aluminum, and nickel. Since Rilsan® coatings can adhere to many different substrates, they can be used in many different applications that span a variety of industries. Some applications these fine powder coatings can be used in include the following:
Busbar
Heat exchangers
Battery racks
Rotors and stators
Switchgears
Chiller plates
and more
Rilsan® fine powder coatings are versatile, allowing them to be used with other processing materials depending on industry needs. They can provide you with the same end benefits in terms of flexibility, chemical resistance, electric strength, and faster production rates without compromising material quality. Rilsan® fine powder coatings are available in many different colors and are easy to use. If you want to learn more about these fine powder coatings, reach out to ChemPoint today.
