Experimental analysis of reversible processes in soft magnetic materials

We present measurements of the small-field magnetic response of non-oriented 1.8 wt% SiFe and rapidly-quenched 6.5 wt% SiFe as a function of various magnetic histories. The first part of the return branch originating from a given turning point (H/sub 0/,B/sub 0/) was fitted by the quadratic law B-B/sub 0/=/spl mu//sub rev/(H-H/sub 0/)/spl plusmn/(b/2) (H-H/sub 0/)/sup 2/ and the dependence of /spl mu//sub rev/ and b on (H/sub 0/,B/sub 0/) and magnetic history was studied. /spl mu//sub rev/ and b approximately follow the laws /spl mu//sub rev//spl prop/[1-(B/sub 0//B/sub m/)/sup 2/]+const, b/spl prop/[1-|B/sub 0//B/sub m/|], /spl mu//sub rev//spl prop/ exp[-H/sub 0//sup 2//2/spl sigma//sub /spl mu///sup 2/]+const, and b/spl prop/exp[-H/sub 0//sup 2//2/spl sigma//sub /spl mu///sup 2/].>