magnet generally refers to neodymium-iron-boron magnet, which is mainly composed of rare earth praseodymium-neodymium and alloy of common element iron. At present, this material is widely used in the market. However, it is common for magnets to encounter weakening or disappearance of magnetic force during use. We summarize the following reasons for demagnetization of magnets:

: magnet injection retreat or demagnetization, and the temperature resistance of neodymium-boron N series is 80 ℃, sometimes injection molding is basically above 120 ℃, so a short time of 2 seconds to 3 seconds of injection molding may cause partial demagnetization imagination.

2: magnet degaussing after hot pressing, often using glass fiber plate hot pressing, temperature above 150 ℃.

3: Magnet demagnetization after oven baking.

4: The magnet material contains too much impurities resulting in weak magnetic field. This is the common result of most cheap buyers. Because the quotation is more than three, pick the manufacturer with the lower quotation. Clearly, the customer's request is to use the N35 brand, the results of the low price of the bad manufacturers on the use of N28, N33 materials, customers do not expect to be able to detect, if the amount of 30K, do you use a magnetic flux meter to slowly measure it? (short 6 months to appear demagnetization, fast two months to appear demagnetization), a reliable and stable supplier is really important. How can you use N35 materials to make it for you without that price? And some merchants use magnets for packaging. Anyway, it's okay to suck, and the materials are rubbish.

5: Impact causes the magnet to demagnetize, such as high-frequency impact, etc. Special care should be taken during transportation.

6: The material contains metal, which causes the magnet to be powdered, etc.

7: High magnetic field environment test magnet itself magnet force disappears or N/S pole changes (magnetizing machine demagnetizing machine).

Summarizes the above demagnetization (degaussing) causes are basically 90%. There are 4 points: high temperature demagnetization, material problem demagnetization, high frequency impact demagnetization, and high magnetic field demagnetization.