268 



BELL SYSTEM TECHNICAL JOURNAL 



Further discussion of "Metallurgy and Magnetism" is given in an exxel- 

 lent small book of this title by Stanley. '■• 



Effect of Composition 



Gross Chemical Composilioii 



The effect of com])osition on magnetic properties will now be considered, 

 using as examples the more important binary alloys of iron with silicon, 



10^x24 



500 qT 



30 40 60 60 70 80 



PER CENT NICKEL IN IRON 



Fig. 18 — Variation of Bs and B wilh the composition of iron-nickel alloys. 



nickel or cobalt, on which are based the most useful and interesting mate- 

 rials. The iron-silicon alloys are used commercially without additions, the 

 iron-nickel and iron-cobalt alloys are most useful in the ternary form; and 

 many special alloys, for example material for permanent magnets, contain 

 four or live components. 



J'"igure 17 shows four im])ortant properties of the iron-silicon alloy's of low 

 silicon content, after they have been hot rolle<l and annealed. The commer- 

 cial alloys (3 to 5% silicon) are the most useful because they have the best 



' J. K. Stanley, Metallurgy and Magnetism, Am. Soc. Metals, Cleveland (1949). 



