FACTORS AFFECTING MAGNETIC QUALITY 



253 



ATOMIC PER CENT COBALT 

 30 40 50 60 



Co 



^7 + MELT 



'^ 



7 + MELT 



7 (face-centered) 



MAGNETIC 

 TRANSFORMATION ,- 



TRANSFORMATION 



400 - 



«^ + 7 I 7+ 



7+e 



(b). 



I , I ( 



Fe 



40 50 60 



PER CENT COBALT 



Co 



Fig. 2 — -Phase diagram of iron-cobalt alloys. 



Fig. 3— Photomicrographs of remalloy (12% Co, 17% Mo, 71% Fe) showing the pre- 

 cipitation of a second phase in the specimen containing an excess of carbon (0.06%) 

 Courtesy of E. E. Thomas. Magnification: (a) 50 times, (b) 200 times. 



