China Neodymium And Ferrite Magnets Manufacturer & Supplier 
In acid, alkaline or other serious corrosive environments and magnet surface insulation requirements, NdFeB magnets generally use thermosetting coatings for surface protection, the current industry commonly used spray epoxy, Everlube, ZnAl and Teflon coatings.
Spray-Epoxy Resin Coating
Epoxy resin has excellent water resistance, chemical resistance and adhesion, and sufficient strength. In particular, the absorption and permeability of epoxy resin is the smallest among various resins. However, the process of applying organic-coated epoxy resin coatings by spraying requires the resin to be diluted with organic solvents, which leads to serious environmental pollution.
Black epoxy coated curved strong magnets
Spraying - Everlube Coatings
Everlube (10047) is a coating developed by Everlube USA specifically for magnets and their related applications. 10047 has many advantages over other coating processes. It protects against wear and corrosion, and also improves assembly with other parts. Due to the excellent properties of 10047, many magnet customers abroad specify this coating. However, the cost of Everlube 10047 coating is higher compared to typical coatings and may increase manufacturing costs.
Spraying - ZnAl Coating
Zn-Al coating (chromium-free Zn-Al coating) technology is developed on the basis of Dacromet coating research, so it is very similar to Dacromet coating in its coating characteristics, with no hydrogen embrittlement, high corrosion resistance, environmental protection, etc. The main difference in Dacromet coating has a good bonding function and passivation of chromic anhydride acid, which has been replaced by chromium-free binder and passivator. However, due to its poor mechanical properties (wear resistance and hardness), its application is limited to a certain extent. Zn-Al coatings are usually prepared on the surface of sintered NdFeB magnets by spraying process in industry.
Spray-Teflon Coating
Teflon (Teflon) coating is well known for its excellent non-adhesive, corrosion resistance and high temperature resistance, and is widely used in a variety of industrial and domestic applications.Teflon coating is able to withstand high temperatures, and the common range of temperature resistance is up to 260 degrees Celsius, which is suitable for high-temperature scenarios, such as ovens; it is highly corrosion-resistant to acids, alkalis, and other chemicals, and is suitable for use in a variety of chemical environments; the coating surface has high hardness and good abrasion resistance, which can extend the service life; Teflon coating is also an excellent electrical insulating material for electrical and electronic fields. The high hardness of the surface of the coating has good abrasion resistance, which can prolong the service life; Teflon coating is also an excellent electrical insulation material, applicable to the electrical and electronic fields.
The above is about the surface protection of sintered neodymium magnet of spraying thermosetting coating introduction, I hope it is helpful to you!
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