Just see a netizen asked a question about the black magnet, ask black magnet is what material, with your question, Xiao Fu here to introduce this kind of black magnet.
Black magnet, that is, a magnet with a black surface, the commonly used shapes on the market are round sheet, ring, square, with a pass, arc, semicircle, and some irregular shapes and so on.
Black rectangular neodymium magnets

Strong magnets are usually not black, but silver or gray. This is because powerful magnets are usually made of materials such as NdFeb, which are themselves silver or grey. However, some strong magnets may be painted black to increase their durability and aesthetics.
What material is black magnet?
There are many kinds of magnet materials that are black on the outside, some are originally black, some are turned black by coating, such as sintered ferrite magnets, injection ferrite magnets, black coated rare earth neodymium iron boron magnets, black epoxy bonded neodymium magnet rings, rubber magnets, etc. are all black magnets. If there are samples that can not be clearly identified, they can be sent to the magnet manufacturer for confirmation.
The above is about what kind of material the black magnet may be. If you need to buy the black magnet for the refrigerator, small black magnet, please send us an inquiry.
This 1mmx1mm miniature circular magnet has a compact size and a surface magnetic field of approximately 2900 Gauss, making it suitable for precision applications with high requirements for magnet size....
This product is a miniature round magnet, made of rare earth NdFeB magnets, belonging to the ultra-small size magnet series, using N35 grade, the specific size is 1.5mm diameter, 1mm thickness, axial magnetization, surface nickel coating, tolerance ±0.05, such as If you are interested in this small magnet product, you can contact us to customize it for you....
Customers from the United States, the United Kingdom, Australia, Japan, Poland and other customers are looking for ferrite cylindrical magnets. Welcome to contact the Courage magnet manufacturer. Our company is located in Dongguan, China. There are many ready-made sizes and low prices. Like the main picture...
The sample is a small-sized Y35 ferrite magnetic block with a specification of 3 × 1.3 × 4mm, magnetized along the length direction, and a surface magnetic field of about 1300 Gauss....
This is a very small rectangular ferrite block magnet, measuring 2.45 mm in length and 1 mm in both width and height. It is magnetised along its length and is barely noticeable when held in the hand....
7.4x6x5mm Ferrite Small Block Magnet Introduction,Material: Hard Ferrite (Ceramic),Shape: Block / Rectangle / Bar,Coating: No Coating,Grade (Chinese Stardard): Y30,Operating temperature: -40°C to 250°C,Delivery time: 7-15 days,Magnetization direction: thickness....
U-shaped neodymium magnets are a type of high-performance permanent magnet material with a structure resembling the letter ‘U’. Manufactured from sintered neodymium-iron-boron, they are characterised by high magnetic energy product....
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