Large Cryogenic Magnetostriction Induced by Hydrostatic Pressure in MnCo 0.92 Ni 0.08 Si Alloy.

Giant magnetostriction could be achieved in MnCoSi-based alloys due to the magneto-elastic coupling accompanied by the meta-magnetic transition. In the present work, the effects of hydrostatic pressure on magnetostrictive behavior in MnCoNiSi alloy have been investigated. The saturation magnetostriction (at 30,000 Oe) could be enhanced from 577 ppm to 5034 ppm by the hydrostatic pressure of 3.2 kbar at 100 K. Moreover, under a magnetic field of 20,000 Oe, the reversible magnetostriction was improved from 20 ppm to 2112 ppm when a hydrostatic pressure of 6.4 kbar was applied at 70 K. In all, it has been found that the magnetostrictive effect of the MnCoNiSi compound is strongly sensitive to external hydrostatic pressure. This work proves that the MnCoSi-based alloys as a potential cryogenic magnetostrictive material can be modified through applied hydrostatic pressure.