THE JOULE MAGNETOSTRICTIVE EFFECT IN A GROUP OF COBALT-IRON ALLOYS

Abstract

In the course of studying various ferromagnetic rods, a group was found which showed a wide variation in the type and magnitude of the changes in length which occur when they were magnetized longitudinally. This collection included rods of iron, nickel, cobalt and alloys of cobalt‐iron. In a later paper it is proposed to correlate the final results in this paper with the mechanical hardness, elastic properties, hysteresis loss and change in resistance due to a magnetic field. In making the following study a new extensometer and recording camera were used. These are described in the following pages.