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BELL SYSTEM TECHNICAL JOURNAL 



occurs in high fields, of the order of 10 to 100 oersteds; as may be seen 

 in Fig. 7, its beginning corresponds to the place where the curves 

 suddenly bend over, away from the almost vertical section. It is 

 only when the field is applied to a single crystal in the direction of 

 easiest magnetization that this last process is avoided. When the 

 field is applied in the direction of most difficult magnetization, the 

 rotational process begins at a field-strength lower than in any other 

 case. 



One other important property of single crystals is accounted for by 

 this picture. This property is evident when a field is applied to a 

 single crystal in a direction not parallel to a principal axis. For 

 example, let the field be applied 30 degrees from a cubic axis of an iron 

 crystal, as indicated in Fig. 11 by the longest arrow. As this field is 



CRYSTAL AXIS (EASY MAGNETIZATION) 



Fig. 11 — Vectors represent B-H in iron, increasing in magnitude as the magnetic 

 field (H) increases. First B-H is parallel to H (1); then as B-H increases it deviates 

 in direction from // (2); and finally in high fields is again parallel to H (3). 



increased from zero, the magnetization will correspond in magnitude 

 and direction to the other arrows shown. First it is parallel to the 

 field, but as the field increases it deviates toward a direction of easy 

 magnetization until finally it is saturated in that direction. As the 

 field is increased further, the magnetization approaches again the 

 direction of the field and finally is saturated in this direction. Theory 



