MOLYBDENUM PERMALLOY FOR INDUCTANCE COILS 



389 



the cores are heated in an atmosphere of hydrogen, with the attain- 

 ment of high core permeability and low hysteresis loss. The ability 

 of the insulating material to withstand such a heat treatment testifies 



300 



200 



100 

 80 



60 

 50 



40 

 30 



0.1 



0.2 



0.3 0.4 0.5 0.6 0.7 0.8 

 METALLIC PACKING FACTOR (p) 



300 



200 



lOOZ 



UJ 



O 



20 tr 

 O 

 u 



z 

 < 



8 ^ 



Fig. 2 — Relation between metallic packing factor, permeability 

 and percentage dilution. 



to its extreme stability and recommends it in preference to organic 

 materials. 



An essential core requirement of precision inductance coils is that 

 the permeability remain unaltered during the life of the coil. The 

 greatest difficulty with cores having no air gaps is the large and more or 



