FACTORS AFFECTING MAGNETIC QUALITY 



257 



are [100] (parallel to one of the crystal axes), and [111] (as far removed as 

 possible from an axis). The magnetic properties in the two directions are 

 different because different "views" of the atomic arrangement are ob- 

 tained in the two directions. 



Production of Magnetic Materials 



In the preparation of magnetic materials for either laboratory or commer- 

 cial use there are many processes which influence the chemical and physical 



10^X650 



"0 2 4 6 8 10 12 14 16 18X10^ 



INTRINSIC INDUCTION, B-H, IN GAUSSES 



Fig. 9 — Dependence of permeability on crystallographic direction. Williams. 



structure of the product. The selection of raw materials, the melting and 

 casting, the fabrication and the heat treatment, are all important and must 

 be carried out with a proper knowledge of the metallurgy of the material. A 

 brief description of the common practices is now given. For further dis- 

 cussion the reader is referred to more detailed metallurgical books and ar- 

 ticles. 



