A BRA UN TUBE HYSTERESIGRAPII 



305 



of iron having the thickness d and the width c. The sample is being 

 magnetized in the direction perpendicular to the plane of the paper. 

 The magnetization produces eddy currents and we shall assume that 

 the elements of induced current flow in circuits like the shaded element 



Fig. 12 — Cross-section of specimen. 



of area at the distance x, — x on the horizontal axis and the distance 

 (cld)x, — {cld)x on the vertical axis, with the corresponding widths 

 dx and (cfd)dx. The current density ix which is induced in the 

 elementary circuit is 



tx = 



10- 



1 



cd 



1 



dt p 4(c2 + c^2) ^ 



(16) 



The flux (fez is the total flux enclosed by the elementary circuit, and p 

 the specific resistance of the iron. Within the elementary area itself 

 the flux difx is the sum of the fluxes produced by the applied field 

 and by the field due to the eddy currents external to the elementary 

 area. If it is now assumed that the applied field is just passing through 



