Choice of material in the design of permanent magnet flux sources

To determine the temperature dependence of the magnetization of three commercial high energy product permanent magnet materials under conditions approximating those in a permanent magnet circuit, a method is devised whereby measurements are made at values of μ_L= B/μ₀H that remain constant as the temperature is varied. All the values of μ_L used are on the same spherical sample for any given material. The values of μ_L range from zero to ten thousand to mimic almost any circumstance likely to be encountered in most real permanent magnet circuits. The method of measurement is described, and an example of the material selection procedure for an actual magnetic circuit is given