You can download the demagnetization files for the following magnet grades free. Each excel file contains the digital Demagnetization Curves at various temperatures for a specific grade.
MagWeb’s digital demagnetization curves also list the coordinates of the Knee Point of a magnet. Operating a magnet beyond its knee point will demagnetize it, thereby degrading its performance. (Unfortunately, manufacturer’s demagnetization curves do not list this critical knee point data)
Version 2 lists this Knee Point of a grade for each temperature. This knee point is identified by 4 decimals. The data shown in green color refers to data above the knee point. Magnets should always be operated within the green-colored data range to prevent demagnetization. This knee point data aids the fail-safe design of magnets. It is available only at MagWeb.
Table. Demagnetization Curves for Magnets (download link)
Category Code | Category | Manufacturer Grade |
AM | Neodymium Magnets | Arnold Magnetics N40UH |
AM | Neodymium Magnets | Hitachi Metals NMX-48BH |
BM | Samarium Cobalt Magnets | Dexter Magnetics S3218 |
BM | Samarium Cobalt Magnets | Electron Energy Corp 20-T500 |
CM | Bonded Molded Magnets | BMG 2560 |
CM | Bonded Molded Magnets | Kolektor 86EP |
DM | Ferrite Magnets | Dexter Magnetics HF085 |
DM | Ferrite Magnets | TDK FB138 |
EM | Alnico Magnets | HPMG LNGT18 |
EM | Alnico Magnets | Thomas & Skinner Alnico 9 |