An alignment evaluation method for polycrystalline Terfenol-D based on magneto striction effect

The paper presents the alignment evaluation method based on magnetostrictio n of the aligned grains. The method can be used to evaluate the alignment e ffects in polycrystalline Terfenol-D, fabricated by various technologies. I n this evaluation method, the contributions to the effective magnetostricti on and the volume fraction of the grains in polycrystalline Terfenol-D with every existing crystallographic orientation were considered. We proposed a concept of the contribution factor (F-H K L) of the oriented grains, which is used to determine the contributions to the effective magnetostriction. The parameter (F-H K L) is obtained from calculating the ratio of the satur ation magneto striction of the oriented grain to that of the single crystal with < 111 > orientation. The volume fraction of the oriented grain is obt ained from the inverse pole figure data. Based on the contribution factor a nd the volume fraction, an equation of alignment evaluation was established , which can be used to calculate quantitatively the alignment effect. Throu gh the comparison between the measured and calculated results, we have foun d that the differences of alignment evaluation parameters are basically equ ivalent to those of their magnetostriction strains. This proves the feasibi lity of the evaluation method. (C) 2001 Elsevier Science B.V. All rights re served.