Domains of Reverse Magnetization

An experimental study by the powder deposit technique has been made of interesting domains of reverse magnetization which arise when an initially saturated crystal of silicon-iron is demagnetized. Two cases have been studied with the crystal ( a ) as perfect as possible, and ( b ) with an artificial defect made at one end to provide controlled demagnetization effects. They show that imperfections in the surface are very important in determining the observed demagnetization phenomena. The surfaces of the crystal may themselves act as imperfections.