Coatings and Platings
Magnetic Component Engineering offers the following types of standard finishes on permanent magnets:
Depending on the application and material being used, the selection of coating is important.
When using the magnet in a high vacuum environment, a metallic coating is recommended for Neodymium Iron Boron. Nickel and K1228 are the most suitable. Alnico, Ceramic and Samarium Cobalt magnets need not be plated for this application.
When using Neodymium Iron Boron magnets in non-vacuum or low vacuum applications (10-3 Torr and higher pressures), the phenolic resin coating is typically the preferred choice. Again, alnicos, ceramics and samarium cobalts need not be coated.
Samarium Cobalt generally is used without coating or plating because it typically does not show signs of oxidation during normal use. Occasionally, coating with PR1010, or an epoxy coating may be desired if cleanliness is very critical. Discuss your application with our sales engineers to determine which finish is best if required.
Neodymium Iron Boron magnets are prone to oxidation and coating or plating is recommended.
Ceramic magnets cannot be plated since the material is non-conductive. Organic coatings such as phenolic resin are the best choice if coating is required.
Alnico magnets are not typically coated or plated.
Shapes such as blocks and discs and rings are easier to coat. Tubes (aspect ratios of internal diameter to axial length being 1:2 or greater) become more challenging since coating needs to be able to enter the internal diameter. Aspect ratios of 1:3 and higher, especially for diameters under 0.50” will leave areas with extremely thin coating thickness or uncoated areas in the diameter. If it is critical to coat the inside diameter, alternatives do exist and you are encouraged to contact us.
MCE uses proprietary methods of pre-processing the materials before plating or coating. Plating or coating magnets is quite different from coating metals, and the pre-processing is a very important part of the plating or coating treatment.
Contact MCE to discuss your application; our engineers will assist you with writing the correct specifications for your requirement.