How to judge whether a strong magnet is good or not？

The sales competition pressure for powerful magnets in the market is increasing year by year, and many magnet manufacturers choose to use inferior raw materials to reduce costs in order to gain a better competitive advantage in the market. So when purchasing a strong magnet, we must know how to distinguish the quality of the strong magnet, so that we can buy a relatively high-quality strong magnet.
Identification method:
The quality of a powerful magnet is mainly analyzed from two aspects:
(1) Product performance
(2) Product appearance
Performance of strong magnets: There is a unified standard for the performance of strong magnets. Of course, the premise is that products produced by legitimate manufacturers need to consider the relevant parameters of strong magnets when distinguishing, such as magnetic energy product, coercive force, residual magnetism, and other related properties. The conventional measurement method is to use a Gauss meter or flux meter to distinguish the magnetic energy product of strong magnets of different specifications and sizes, while more professional ones require the use of a static magnetic characteristic tester.
Strong magnet appearance:
The appearance inspection of powerful magnets mainly includes five categories
1. Is there any scratch on the appearance of the magnet (including scratches, line marks, knife marks, etc.)
2. Are there any pits on the surface of the magnet (including pits, pits, bubbles, scars, slag layers, local thickness, electroplating nodules)
3. Is there any crack on the surface of the magnet (including cracks, cracks, etc.)
4. Is there any chipping on the surface of the magnet (including chipping, chipping, and material residue)
5. Is there any sand holes on the surface of the magnet (including sand holes, pores, pinholes, particles, etc.)
Overall, it depends on whether the magnet has missing edges or corners, whether the electroplating layer is intact, and whether the size meets the design requirements;
Neodymium, iron, and boron are generally electroplated to protect them from corrosion and rust. In general, magnets of the same specification can be placed on a surface that can be adsorbed, and the size of the magnetic force can also be easily distinguished by hand feeling.