Nd-Fe-B permanent magnet materials have developed rapidly since 1983 because of their excellent magnetic properties. At present, it has been widely used in Electromechanical, communication, instrumentation, computer, medical equipment and other fields.
As a mature metal surface treatment technology, electroplating has been widely used in the anti-corrosion field of Nd-Fe-B magnet. Compared with ordinary parts electroplating, the particularity of Nd-Fe-B electroplating is that it is difficult to obtain a coating with good adhesion, the relationship between coating thickness and magnetism is difficult to coordinate, and the coating surface is easy to be damaged. This paper will elaborate the particularity of Nd-Fe-B electroplating equipment from the following aspects.
Nd-Fe-B products are mostly small parts, mainly barrel plating. The drum is the most important part of the whole equipment. Only by selecting the appropriate roller can we produce high-quality products.
1.1. The drum size Nd-Fe-B material is a multiphase structure with different phase potentials, especially the nd rich phase at the grain boundary has the lowest potential, forming a primary cell with other phases, causing electrochemical corrosion. Its corrosion rate is much higher than that of ordinary steel parts. Therefore, the coating should be deposited as soon as possible after the NdFeB parts enter the drum to prevent the surface oxidation process.
1.2. There are many thin parts in Nd-Fe-B products , Due to the “wall sticking” phenomenon of parts, it is easy to cause coating quality problems, such as “roller eye” and uneven thickness. Increasing the roller speed is a good way to solve the problem of part sticking to the wall. If the speed of the drum is fast, the parts roll well and the probability of adhesion to each other is very small. However, due to the brittleness of Nd-Fe-B material, if the parts are rolled too hard in the drum, different degrees of surface damage will occur. In order to ensure that the parts roll evenly in the drum, it is necessary to increase the speed of the drum, but in order to ensure that the damage degree of the parts is small at high speed, the diameter of the drum can be reduced. The smaller the diameter of the roller, the smaller the drop when the parts roll and fall, the smaller the collision strength between the parts, and the smaller the damage on the surface of the parts.
2.There are a variety of parts for Nd-Fe-B products in the production line , The roller used for electroplating is small in size , Large quantity , And electroplating production is large , Product quality requirements are high , Choosing a suitable production line is very important.
Post time: Jul-26-2021