ELASTIC CONSTANTS AND LOSSES IN NICKEL 



973 



along tool), for tlie shear mode with particle motion along [lIO]. Fields of 

 about 10,000 were attainable but a maximum field of about 6000 was usu- 

 ally used. The velocity increases by 2.6 per cent at the saturated value. 

 On decreasing the field to zero the velocity drops below the original value 



2.8 



2.4 



2.0 



1.6 



5I>° 



1.2 



0.6 



0.4 



-0.4 



1000 2000 3000 4000 5000 



MAGNETIC FIELD STRENGH,H,IN OERSTEDS 



6000 



Fig. 2 — Change in velocity in percent from demagnetized value as a function of the 

 magnetizing field for a shear wave in a (110) section when the particle velocity e is 

 along the [iTOl direction and the field H along the [001] direction. 



for the demagnetized state, but it has practically the initial value when the 

 crystal is again demagnetized. The lower value of velocity for the return 

 curve indicates that the free energy is lower for some arrangement of the 

 elementary domains other than the demagnetized state. 



Figure 3 shows the attenuation in decibels per trip as a function of mag- 



