THE MAGNETOSTRICTION OF COFENIMO METALLIC GLASSES MEASURED WITH A TUNNELING TRANSDUCER

The longitudinal magnetostriction as a function of the Co/Fe content of the metallic glass series Co(72-x)Fe(x)Ni3 Mo1Si12B12, for 0 less-than-or-equal-to x less-than-or-equal-to 10, is reported. The measurement is performed using a novel technique, based on electron tunneling, which provides a highly sensitive, noncontact, quasi-dc and direct measurement of magnetostrictive strains. The minimum value of the longitudinal magnetostriction measured is (-1.65 +/- 0.24) ppm for 0% Fe, and the maximum (in this composition range) is (2.51 +/- 0.15) ppm for 10% Fe, with a zero-magnetostriction composition of 5.25% Fe. These data are compared to those previously reported for a similar metallic glass series, but with higher Mo content. Increasing the Mo content in these glasses is shown to decrease the Fe content at the zero-magnetostriction composition point.