Main >>Applications >> Sample problems >> Attraction of the cylindrical magnet to the steel plate
Cylindrical permanent magnet is pulled toward the ferromagnetic plate.
Axisymmetric problem of magnetostatics
D = 2" (50.8 mm) - magnet diameter;
l = 0.65" (16.51 mm) - magnet thickness;
t = 2" (50.8 mm) - plate thickness;
magnet grade N35, Hc = 954930 A/m, Br = 1.26 T;
relative magnetic permeability of plate μsteel = 1000.
Calculate the pulling force of the magnet toward the steel plate.
To calculate the pulling force accurately, and avoid integration along the edge dividing media with large difference in magnetic permeabilities, we place the magnet at a small distance δ = 0.005" (0.127 mm) from the steel plate. Integration contour is drawn in the air around the magnet.
510 N (112.3 lb, 1 lb = 4.54 N)
* Reference: www.kjmagnetics.com.