How to Solve the Corrosiveness of NdFeB Magnets
The advantages of NdFeB are high cost performance and good mechanical properties; the disadvantage is that the Curie temperature point is low, the temperature characteristics are poor, and it is easy to be pulverized and corroded. It must be improved by adjusting its chemical composition and adopting surface treatment methods. , in order to meet the requirements of practical use.
Ferrite is a ferromagnetic metal oxide. In terms of electrical properties, the resistivity of ferrite is much larger than that of metal and alloy magnetic materials, and it also has higher dielectric properties. The magnetic function of ferrite is also manifested in high permeability at high frequencies. Therefore, ferrite has become a widely used non-metallic magnetic material in the field of high frequency weak current.
NdFeB belongs to the third-generation rare earth permanent magnet material. It has the characteristics of small size, light weight and strong magnetic properties. It is the magnet with the best performance and price ratio. The advantages of high energy density make NdFeB permanent magnet materials widely used in modern industry and electronic technology. In the state of bare magnetism, the magnetic force can reach about 3500 Gauss.
NdFeB magnets are very susceptible to corrosion. Therefore, most of the finished products need to be electroplated or painted. The commonly used surface treatments include: nickel plating (nickel copper nickel), zinc plating, aluminum plating, electrophoresis, etc. If working in a closed environment, phosphating can also be used.
NdFeB magnets are now widely used and rapidly developing magnet products. It has only been more than 20 years since NdFeB has been widely used since its invention. Due to its high magnetic properties and ease of processing, the price is not very high, so the scope of application can be expanded rapidly. Now, the magnetic energy product of commercial NdFeB can reach 50MGOe, which is 10 times that of ferrite. NdFeB is also a powder metallurgy product, and the processing method is similar to that of samarium cobalt. Now, the maximum working temperature of NdFeB is around 180 degrees Celsius. If it is used in harsh environments, it is generally recommended not to exceed 140 degrees Celsius.