ELASTIC CONSTANTS AND LOSSES IN NICKEL 



975 



limit on account of the "morphic" effect discussed in another paper.* If 

 we average the two values the effective elastic constant for saturation be- 

 comes 



c'n - cU = 0.954 X 10" dynes/cm«. (5) 



Measurements for the field along the thickness did not produce saturation 



and are not shown. 



2.4 



2.0 



1.6 



1.2 





0.8 



0.4 



•0.4 



1000 2000 3000 4000 5000 

 MAGNETIC FIELD STRENGTH, H, IN OERSTEDS 



6000 



Fig. 4 — 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 is along 

 the [110] direction and the field along the [110] direction. 



Figures 5 and 6 show similar measurements for the other shear mode 

 (Shear 2 of Table I) for two directions of the magnetic field. Averaging 

 the two limiting values, the constant Ca at saturation becomes 



cIa = 1.22 X 10^2 dynes/cm^ (6) 



The Q and decrement for this case become approximately 110 and 0.028. 



