Demagnetization Curves / BH Curves

A demagnetization curve describes the magnetic qualities of a magnet more completely than a single number like Pull Force or Surface Field. It provides information about the strength of the magnet, how hard it is to demagnetize, and how a magnet’s shape (or use in a magnetic circuit) affects matters.

Sintered NeFeB – Demagnetization Curves

Demagnetization curve provides information about the magnetic characteristics of a magnet,It provides information about the strength of the magnet, how hard it is to demagnetize, and how a magnet’s shape (or use in a magnetic circuit) affects matters. When a permanent magnet is fully magnetized, its magnetic domains are aligned. Certain conditions such as temperature and reverse magnetic fields can cause some of the domains to lose this alignment and reverse, triggering the magnet to lose some or all of its magnetic field.

Bonded NeFeB – Demagnetization Curves

SDM manufactures bonded NdFeB permanent magnets in grade BNP-2，BNP-4，BNP-6, BNP-8L, BNP-8, -8SR, BNP-8H, BNP-9, BNP-10, BNP-11, BNP-11L, BNP-12, which can be coated with back or grey epoxy. Most customers usually require ring magnets made bonded NdFeB material with multi-poles through diameter or radial magnetization. We also customize bonded magnets in arc, block shapes, etc. For Example :

SmCo Magnets – Demagnetization Curves

SmCo magnets rank similarly in strength to neodymium magnets but have much higher temperature stability and higher coercivity. They can operate at temperatures up to 525°F (300°C). In addition, they have a very high resistance to demagnetization and to corrosion. Sm1Co5, Sm2Co17 For Example :

AlNiCo Magnets – Demagnetization Curves

Alnico alloys consist of aluminum, nickel, cobalt, copper, and iron. Some grades have titanium and some manufactures also use additions of silicon, columbium zirconium, or other elements to enhance the magnetic properties. These alloys are formed by foundry processes as previously noted. The magnetic performance is developed by heat treating the castings. The heat treat process for most of the grade includes the application of a magnetic field to produce domain alignment. Sintered Alnico2, Alnico5, Alnico8, Cast Alnico5, Cast Alnico5-7, Cast Alnico8 For Example :

Ferrite / Ceramic Magnets – Demagnetization Curves

Ceramic (Ferrite) Magnets – This family of magnetic materials is one of the most commonly used. It is produced in Grades 1, 5, and 8. It is excellent at elevated temperatures with a maximum service temperature of 450C. Conventional standards of sintered ferrite isotropic / anisotropic magnet, y10t, y25, y30, y35 For Example :