Surface Treatment of Neodymium magnets
Corrosion Resistance of Neodymium magnets
A neodymium-based sintered magnet is liable to oxidization or corrosion because it has for its main components neodymium (Nd) and iron (Fe) and is composed of several phases in a crystalline structure. It is subject to electrochemical corrosion under the presence of a small amount of acid, alkali or water; the magnet rusts and demagnetizes as rusting progresses. Although it remains stable for many hours when it is allowed to stand in a dry atmosphere, it should be surface-treated as a preventive measure for the presence of humidity or a rise in temperature, an event often encountered in a general operating environment. This treatment may become unnecessary when it is used in a hermetically sealed system or in a low-corrosion environment.
The magnet does not corrode when exposed to general organic solvents or adhesives. However, customers are advised to contact Magpole Technology sales office beforehand if cutting or grinding of any neodymium magnets products is intended. If washing and drying process is involved in processing of the neodymium magnets on the customers side, cautions must be undertaken concerning residual water or condensation of moisture on the magnets. Storing the magnets in a dry atmosphere or in an inert gas is strongly recommended.
Surface treatment of neodymium magnet
Neodymium magnets has improved corrosion resistance of the base material itself as a result of structural refinement and compositional uniformity of sintered constituents. Moreover, its reliability is enhanced considerably by the application of surface treatment technologies such as aluminum and nickel coatings. Additionally, greater importance is attached to surface coatings in terms of not only corrosion-resistance performance but also other factors such as adhesive durability and electrical insulation quality, the recently increasing requirements for magnets used in motors. We have developed environmentally sound processes and products that meet these requirements. Customers may use the neodymium magnets products with confidence with regard to these aspects. Our surface treatment technology is in compliance with international environmental standards, such as the RoHS directive and ELV directive.
Customers are strongly advised to consult with Magpole Technology sales office for technical assistance concerning the surface treatments in order to choose appropriate treatment processes and product types suitable for the intended applications according to the specific usage environment and required characteristics.