抄録
New distance sensors are presented which utilize a large Barkhausen effect of amorphous magnetostrictive wires. Only one domain wall is propagated in the direction of the wire axis with a drive magnetic field H when the condition H*>H>H0 is satisfied throughout the wire length, where H* is the critical field of nucleation of a reverse domain, and H0 is the critical field of domain wall displacement.
A distance sensor with a nolinearity of less than 0.7%FS throughout a 1000 mm distance is established using a cold-drawn and then heat-treated Fe77.5Si7.5B15 amorphous wire of 30μm diameter and 1400 mm length, in which the wall velocity vw=2Ms(H-H0)/β is controlled by increasing H*.
