Dynamic magnetomechanical properties of terfenol-D/epoxy 1-3 particulate composites

This paper describes the effect of particulate crystallographic orientation on the dynamic magnetomechanical properties of Terfenol-D/epoxy 1-3 magnetostrictive particulate composites. Two different types of composites with approximately 50 % Terfenol-D volume fraction were fabricated for comparison with [112]-textured monolithic Terfenol-D. In the first type, needle-shaped, [112]-oriented particles cut from the monolithic Terfenol-D were used and in the second type, irregular-shaped, randomly oriented particles ball-milled from the monolithic material were employed. Elastic moduli ( E33Hand E33B), dynamic strain coefficient (d33), and magnetomechanical coupling coefficient (k33) were investigated as a function of bias field. Both composites demonstrate similar property trends with the negative- ΔE, d33, and k33values maximizing near 30 kA/m. The maximum values achieved in the oriented type are up to 67 % larger than the non-oriented type and approaches 65 % of the monolithic Terfenol-D. The property improvement in the oriented type is shown to be attributed to [112] preferential particulate orientation.