After the factory production and processing of ndfeb products generally like blank color, our magnet manufacturer name & other;
Black piece & throughout;
, not by electroplating ndfeb magnet is very easy to corrode.
The final finished products need to be mature plating or coating process.
Common electroplating processing includes: nickel plating, nickel and copper, nickel, zinc, aluminum plating, electrophoresis, etc.
If the work environment is closed environment, but also for phosphating process.
1, the root cause: sintered ndfeb permanent magnet materials of neodymium high chemical activity, the standard electrode potential is E0 (
431 V, sintered ndfeb permanent magnet itself for multiphase structure, Nd - among them
Rich phase of chemical activity, material within each phase electrochemical potential difference between the larger.
In the electrochemical environment, easy to produce electrochemical corrosion, as grain boundary phase of anode (
Will take on the big corrosion current, as the Lord of the cathode phase (
For low current, and finally form the corrosion characteristics of small anode cathode, accelerated the intercrystalline corrosion, eventually lead to the magnets because of corrosion and damage.
2, the structure of sintered ndfeb magnet itself: the powder metallurgy method, the low density of sintered ndfeb magnets, magnet internal porosity is high, and the surface of the magnet cannot the oxide film formation, in the event of oxidation, magnet internal pore will become corrosive medium, such as oxygen quickly spread fast corrosion channel, can occur within the magnet chain reaction, the oxidation corrosion magnets itself.
3, harmful impurity in the magnets, each link in the production of sintered ndfeb magnet, because of the influence of the production process, equipment, human factors, will lead to internal may contain magnets H, O, N, S, Si, C, Cl and chloride and other harmful impurities, including on the corrosion performance of magnet hazard is one of the most serious harmful impurities O, Cl and chloride.
4, the influence of the working environment: sintered ndfeb magnets are widely used in high and low temperature alternating, long-term maintenance free, extreme environment and other fields, sintered ndfeb magnet is rarely used under the condition of room temperature or vacuum environment, so the different work environment on the corrosion resistance of sintered ndfeb magnet put forward higher requirements.
Ndfeb strong magnet manufacturers network is a professional engaged in magnetic materials research and development, production, sales for the integration of high-tech enterprises.
Products are widely used in electric vehicles, energy saving elevator, wind power, sewing machines, air conditioning, micro motor, etc.