PRESSURE-INDUCED GIANT VOLUME MAGNETOSTRICTION IN THE (FE1-XNIX)(49)RH-51 ALLOYS

We present the results on magnetovolume anomalies in (Fe1-xNix)(49)Rh- 51 alloys. At ambient pressure, they exhibit phase transition from the ferro- to the antiferromagnetic state at temperatures decreasing from about 300 to 150 K for x increasing from 0 to 0.036. The thermal expa nsion and compressibility of the alloys with x = 0.025 and 0.045 were measured under high hydrostatic pressure up to 14 kbar. The phase tran sition to the antiferromagnetic state was induced in the alloy with x = 0.045 by critical pressure of about 2.4 kbar. In the result of the p hase transition to the antiferromagnetic state the volume decrease in the both alloys reaches the value of about 0.8%. The critical temperat ure T-t increases under pressure with the ratio of 9 and 13 K/kbar for x = 0.025 and 0.045, respectively. (C) 1997 American Institute of Phy sics.