A magnet will lose some magnetism immediately when it encounters a high temperature that exceeds its own tolerance. How much high temperature does it need? This depends on the coercive force of the magnet, which is usually expressed by the letter after the magnet grade, such as N40H, the maximum magnetic energy product is 40, and H represents the temperature resistance of 120°C. The higher the coercive force, the more metal dysprosium content is added to the magnet. .
How much magnetism will it lose?
It depends on the degree of its magnetic protection, if there is some iron around it will help. Of course, it depends on the temperature. But this is a highly non-linear effect. It does not lose any magnetism until it reaches a certain temperature, and then loses all magnetism quickly. Please note that the amount of magnetism it loses depends on how high the temperature is, not the length of time at a particular temperature. After the magnet reaches a certain temperature, it will lose all the magnetism that it can reach at that temperature.
How long does it take?
For a specific small volume of magnet, demagnetization will occur immediately. However, even in a small magnet, it takes time for heat to transfer from the outer surface to the center. For example, a 1 cm3 part takes several minutes. However, the part of the magnet near the surface will immediately lose its performance. 200°, whether in Fahrenheit or Celsius, is very high for a magnet. Unless you have a special, very advanced magnet (UH or AH or better), you will completely ruin it.
Introduction to the coercivity of each grade of magnet;
Grade n neodymium magnet: low coercivity
Grade m neodymium magnet: medium coercivity
Grade H neodymium magnet: high coercivity
SH grade neodymium magnet: extra high coercivity
Uh grade neodymium magnet: ultra high coercivity
EH grade neodymium magnet: extremely high coercivity
Neodymium magnet grade parameters;
Magnetic property parameters of sintered Nd-Fe-B
High temperature resistant magnets are recommended;
This product is round ferrite magnet with a diameter of 9mm and a thickness of 3mm, the performance class is Y30, magnetized in the thickness direction, without electroplating protective layer, the magnetic force is usually 700-1000gs, the working temperature is -40°C to +250°C, Suitable for sensors, suction parts, electrical appliances, Hall induction....
This is a very small size rectangular block magnet with galvanized surface, 3mm length, 1.5mm width and height, with very fine tolerance, magnetized by lengthwise direction, mainly used in precision electronics, instrumentation, please contact us if you need to buy....
Flat magnets can be flat square magnets or round magnets. Today's sample is a flat rectangular magnet, with a length of 20mm, a width of 10mm, a thickness of 1.5mm, and a zinc coating on the surface. Thickness magnetization is used for thin workpieces. The use of this relatively flat neodymium rectangular magnet requires special attention....
Looking for suppliers of radial 16 pole ring magnet and multi-level magnetic ring, welcome to contact carrich magnet manufacturers in China. We have more than 10 years of experience in the motor magnet industry. Our products have many specifications and good performance, which are highly praised by customers at home and abroad. We welcome to provide specifications, samples and batch prices....
This is a dedicated to screwdrivers, drills on top of the ring magnet, the material is rare earth neodymium, N38 grade, outer diameter 15mm, height 10mm. hole diameter 7mm, the use of very simple, is to set the magnetic ring in the screwdriver (screwdriver head) on top of the purchase of the hole is recommended to be larger 1mm....
Product name: 9.5mm diameter thickness 1.5mm neodymium intense magnetic,Type of magnet: permanent magnet,Magnet shape: Round,Magnet class: n45,Tolerance: ±0.05,Coating: conventional nickel copper nickel,Pull: About 1.6 pounds,Magnetic strength: about 2200 Gauss....
This is a C8 grade ceramic ferrite block rectangle, with white marks made according to the customer's requirements. The magnet size is 13mm long, 11mm wide and 10mm thick. If you are interested in such a magnet, you can contact us to provide you with samples, prices,...
This is a 6-pole ring magnet made of injection molded ferrite, with an outer diameter of 9.5mm, an inner hole of 1mm, a thickness of 2mm, single-sided 6-pole magnetization, 3 N poles and 3 S poles. It is mainly used for Hall encoder....