Near-zero magnetostrictive glassy metal alloys with high magnetic and thermal stability

摘要

A new series of glassy metal alloys with near zero magnetostriction is disclosed. The glassy alloys have the composition Co_aFe_bNi_cMo_dB_eSl_f, where a ranges from about 68 to 70 atom percent, b ranges from about 2 to 7.5 atom percent, c ranges from about 0 to 8 atom percent, d ranges from about 1 to 2 atom percent, e ranges from about 11 to 15 atom percent and f ranges from about 9 to 14 atom percent with the proviso that the sum of a, b, c ranges from about 72 to 76 atom percent and the sum of e and f ranges from about 23 to 26 atom percent. The magnetostriction of these alloys ranges from about -1 x 10^-6 to +1 x 10^-6 and the saturation Induction is between about 0.6 and 0.8 Tesla. The transition metal content is responsible for the low magnetostriction in these alloys. The metalloid content strongly affects the saturation induction, Curie temperature, and magnetic stability. Magnetostriction is mildly affected by the metalloid composition and a particular range of Si/B ratio for certain iron, cobalt containing alloys wherein the magnetostriction is near-zero and relatively insensitive to the Si/B ratio. The same Si/B ratios also provide high magnetic stability.