Evolution of soft magnetic, mechanical and electrical properties measured simultaneously during annealing of rapidly solidified alloys

Abstract

The structure evolution of some soft magnetic metastables alloys are scanned and studied through some room temperature properties changes employing only one sample submitted to successive heat treatments. These are monitored by changes occurring in room temperature magnetic properties (data obtained from hysteresis loop at 50 Hz and relative permeability at 10 kHz), room and high temperature electrical resistance and dilatometric measurements, all taken simultaneously. The method is applied to study and compare the structural evolution steps towards the most desirable soft magnetic properties of three different soft magnetic alloys of our production: an amorphous alloy of composition Fe 81 B 14 Si 5 , and two nanocrystalline, a Finemet™ (Fe 73.5 Si 16.5 B 6 Cu 1 Nb 3 ) and a Nanomet™ (Fe 81 Si 6 P 4 Cu 1 B 8 ) – type alloys. The technique reproduces the results obtained by traditional methods, and has the advantage of using fewer measuring instruments, sample tests, less time and human resources. In addition, all the experimental data present a high level of detail. With the results obtained, a large quantity of magnetic, electrical and dilatometric data is available to discern the possible applications of these three materials.