Patent ID: 6057766
Filing Date: 2000-05-02
Classification: G08B,H01F,H01L

Abstract:
A magnetomechanical EAS marker, comprising:an active element in the form of a strip of amorphous magnetostrictive metal alloy having a composition essentially of Fe.sub.a Co.sub.b Ni.sub.c M.sub.d B.sub.e Si.sub.f C.sub.9 ; andmeans for applying a magnetic bias at a level H.sub.B to said active element, H.sub.B being greater than 3 Oe;said active element having been annealed to relieve stress therein and having a magnetomechanical coupling factor k, such that 0.28.ltoreq.k.ltoreq.0.4 at the applied bias level H.sub.B ;with 45.ltoreq.a.ltoreq.82; 0.ltoreq.b.ltoreq.40; 0.ltoreq.c.ltoreq.30; 2.ltoreq.d.ltoreq.17; 0.ltoreq.e.ltoreq.28; 0.ltoreq.f.ltoreq.8; 0.ltoreq.g.ltoreq.4 (a-g in atomic percent); and M is one or more of Mn, Mo, Nb, Cr, Hf, Zr, Ta, V; provided that:(i) the combined proportion of Mn, Mo, Nb, Cr, Ta, V, if present, does not exceed 10%; and(ii) the combined proportion of Zr and Hf, if present, does not exceed 15%.