Near-zero magnetostrictive metallic glasses with very high saturation induction

Abstract

The soft magnetic properties of a series of metallic glasses in the Co–Fe–Ni–Mn–B–Si system are described. These glasses have very low values for saturation magnetostriction (+5 to −1 ppm) and some of the highest values for saturation induction (1.1 to 1.3 T) reported for such glasses. Most importantly, the Curie temperture is lower than the crystallization temperature, thus allowing the use of easy, conventional annealing procedures for the optimization of the soft magnetic properties. Initial permeabilities in excess of 17 000 at 1 kHz may thus be achieved for optimal compositions within the system. These metallic glasses offer great promise for applications such as recording heads to be used in conjunction with high coercivity metal tapes.