Magnetic Properties of Pure Iron. 



Table II. 

 Magnetic Properties of Pure Iron. 



365 



Treatment. 



No. of J B( m ax.) 

 Crystals for H 

 per cm. | =95. 



As received 426 



Normalized J 343 



Annealed .. 



Drastically 



annealed 

 Quenched and 1 



tempered ... J 



...} 



276 



9 



6<?0 



18250 

 18550 

 18200 

 18400 

 18400 



B(rem.). 



Ho. 



10400 



2-5 



10000 



2-0 



10000 



2-0 



10000 



4-0 



9600 



5-0 



Hysteresis Brinell 

 loss. Hardness. 



22900 

 21400 

 19200 

 24400 

 34600 



86 

 83 

 74 

 70 

 105 











Fig 



. 1. 











B 





















I&OQO 













— -r- 



:r= r 



r^r^ 



. 



12 OOO 



/ 



i , 





s~~ 



' / 



r" 









1 

 R ooo 1 



1 / 



1 1 



1 ' 



' i 



i i 



i i 





i i 



1 i - 



i 

 i * — 



: B-f 



- Pu 



/ curv 

 re /re 



es for 

 n 



— 



1 



I 

 1 



4. ooo J 



f 

 . 1 





j ' 

 i l 



i i 



■i 



r 



i 

 i 











1 



r 



! 



1 



i 



,' i 



i ' i 

 i r 



j-: i. 



l 1 



r j 



1 L. 



i 



\h\ 



/ divh 



'on = 2 



OH 



of crystals per unit length (the anomalous case of the dras- 

 tically annealed sample will be considered later), and at the 

 same time a corresponding increase in the hysteresis loss per 

 cycle is found. In each case the relationship is an approxi- 

 mately linear one. 



Along with the magnetic results the hardness values of the 

 samples determined by Brinell's method are recorded. The 

 load used was 500 kilograms, and the ball 10 mm. in diameter.. 

 The results are of interest in confirming the general im- 

 pression that magnetic and mechanical hardness go side by 

 side. With the exception, again, of the first sample, if the 

 hysteresis loss per cycle is e and the Brinell hardness H, then 



e = 30H 15 (3) 



