Producing and quantifying induced uniaxial anisotropy in stress annealed polycrystalline Galfenol

A process for inducing uniaxial anisotropy in 18.4 at% Galfenol has been developed, applied, and proven to be reliable. The stress annealing procedure that produces the most consistent results and induces the highest uniaxial anisotropy in FSZM Galfenol (6.35 mm &nullset;) is one modified from previous works by the Magnetic Materials Group at Naval Surface and Warfare Center (NSWC) - Carderock. Further modification in which applied stress is lowered and temperature is raised has proven most successful for stress annealing Bridgman Galfenol (20.83 mm &nullset;) and, in addition, has produced an increase in saturation magnetostriction. Model calculations show predicted tensile operation ranges, on average, of 69 MPa for research grade and 40 MPa for production grade FSZM 18.4 at% Galfenol in which full magnetostriction can be utilized.