MAGNETIC MATERIALS IN RELATION TO STRUCTURE 



37 



of the same alloy after quenching and subsequent aging, the precipitate 

 is visible as rounded particles within the grains and as elongated, 

 needle-like structures within and along grain boundaries. 



150 



125 



<G 100 



800 



700 



600 'n 



200 



12.000 



« 11.000 



< 



O 



z 10,000 



z 

 o 



O 9000 



8000 



y 7000 



18,000 



17,000 



16,000 < 

 O 



15,000 § 



14,000 

 13,000 



300 



400 500 600 700 



AGING TEMPERATURE IN DEGREES CENTIGRADE 



800 



12,000 



Fig. 1 



8 — Effect of aging treatment showing typical age-hardening phenomena for an 

 iron-cobalt-tungsten magnet alloy — Koster^^ 



Koster ''^ reports that these alloys can be rolled or otherwise shaped 

 at sufficiently high temperatures and can be readily stamped at red 

 heat. The alloys machine readily in the quenched condition but on 

 account of the coarse grained structure and consequent brittleness they 

 must be machined without shock. 



