Magnetoelastic behaviour of aluminium substituted Terfenol-D at elevated temperatures

Abstract

Comparisons of the magnetoelastic responses of the highly magnetostrictive compound Terfenol-D (Tb/sub 0.3/Dy/sub 0.7/Fe/sub 1.95/) with aluminium substituted compounds Tb/sub 0.3/Dy(Fe/sub 1-x/Al/sub x/)/sub 1.95/ where 0.05/spl les//spl times//spl les/0.10 in the temperature range 20-300/spl deg/C have been made. In particular measurement of magnetostrictive strain (/spl lambda/), differential strain coefficient (d/sub 33/), and magnetomechanical coupling coefficient (k/sub 33/) have been made against applied dc magnetic field (/spl les/120 kA/m), uniaxial pressure (120 MPa), and temperature. Compared with Terfenol-D, the substituted materials are less anisotropic with larger d-coefficients which require lower bias fields.