Under normal circumstances, the surface of the magnet has a layer of electroplating (of course, there are also requirements for NdFeB without electroplating. The magnets of some concentrators do not require electroplating, and the appearance is similar to ferrite). At this time, there are no rust spots. of. Generally, rust spots appear because it has been in an environment with relatively high humidity, and the air circulation in the working environment is very poor. Magnets should be placed in places with good ventilation and certain temperature differences.
Furthermore, there is not enough time for electroplating, and poor electroplating by the magnet manufacturer is also one of the reasons. This is a problem of the process flow.
Also, if the packaging seal of the strong magnet is damaged, it will also cause oxidation of the strong magnet, causing rust spots.
Another important point is that the dirt on the surface of the magnet is not cleaned well before electroplating, which is also one of the reasons for the appearance of rust spots.
The ground NdFeB magnets will rust. The way to prevent rust is to avoid exposing the surface to water and air. Either simply put it in water (it's better to be alkaline and the carbon dioxide is suppressed) or dry it immediately and seal it (it's better to save it with oil). After grinding, it is recommended to dry it with an ultrasonic dryer immediately to reduce rust. .
NdFeB powerful magnets should avoid the following storage methods:
1. In a place that is too humid and has poor air circulation.
2. When the temperature difference changes greatly, even products that have passed the salt spray test may develop rust spots if they are stored in harsh environments for a long time. If there is no coating on the surface, you can choose to use a desiccant or vapor phase rust inhibitor and store it in a sealed package.
3. Electroplated magnet products should not be placed in high humidity places for a long time, but should be placed in a cool, dry place.