Gyromagnetic Ratios of Iron, Cobalt, and Many Binary Alloys of Iron, Cobalt, and Nickel

Abstract

Gyromagnetic ratios for iron, cobalt, and many binary alloys of iron, cobalt, and nickel were determined by measurements on the Einstein-de Haas effect much as made in the Norman Bridge Laboratory previously. Improvements were made in the method of eliminating large quadrature torques, in the method of reducing disturbances due to the vibrations of the building, in the method of frequency control, in the design of the square wave commutator, and in the design of the rotors. For each series of binary alloys the gyromagnetic ratio was found to vary linearly, or nearly linearly, with the concentration. For the small number of these materials studied in the Norman Bridge Laboratory previously there is good agreement between the new results and the older, both those obtained by the Barnett effect and those obtained by the Einstein-de Haas effect. For the three series of alloys the ranges of $\frac{\ensuremath{\rho}e}{m}$ are approximately as follows: iron-cobalt, 1.03 to 1.08 or 1.09; iron-nickel, 1.03 to 1.05; and nickel-cobalt, 1.05 to 1.08 or 1.09.