Tensile properties of magneto strictive iron-gallium alloys

Iron-gallium alloys can produce magnetostrictions of similar to400 ppm and might function as mechanically robust actuator/sensing materials. Single crystal specimens of Fe-17 at.% Ga were tested in tension at room temperature. Specimens with a [ 1 1 0 ] tensile axis orientation exhibited { 1 1 0}< 1 1 1 > slip and an ultimate tensile strength of 580 MPa through 1.6% elongation. The Young's modulus was 160 GPa in the loading direction with a Poisson's ratio of -0.37 on the ( 1 0 0 ) major face. A specimen with a [ 1 0 0 ] tensile axis orientation exhibited { 2 1 1 } < 1 1 1 > slip and discontinuous yielding. A maximum tensile strength of 515 MPa was observed with fracture occurring after 2% elongation. The Young's modulus was 65 GPa in the loading direction with a Poisson's ratio of 0.45 on the (0 0 1) major face. A sizeable elastic anisotropy of 19.9 was identified for Fe-27.2 at.% Ga accompanied by a Poisson's ratio of -0.75 to produce a large in-plane auxetic behavior. (C) 2004 Published by Elsevier Ltd on behalf of Acta Materialia Inc.