Magnetostrictive Body Centered Iron Base Alloys

wuttiga晶体固体中缺陷的热力学模型包括一个新的场致缺陷特性张量，该模型解释了Fe-Al和Fe-Ga合金中已知的超磁致伸缩的变化。具体来说，该模型表明，下近邻的取代-四方对称的取代对是造成这种效应的原因。研究的目的是通过测量弛豫和非弛豫磁致伸缩常数、弹性和磁各向异性常数以及晶格常数来自一致地确定模型参数。为了推广该模型，研究将扩展到Fe-C-Al和Fe-C-Ga以及可能包含四方对称缺陷对的其他合金。这些研究将导致对体心铁基合金显著磁致伸缩的基本理解。他们将最低限度地使超磁致伸缩系统化，并最大限度地为开发具有显著磁致伸缩的新型合金建立标准。具有磁致伸缩大的材料。000200具有重要的技术价值。该研究将确定体心立方铁基合金的磁致伸缩性质，并为寻找其他磁致伸缩合金建立标准。＊＊＊

0095166WuttigA thermodynamical model of defects in crystalline solids which includes a novel field induced defect property tensor accounts for the known variation of the excess magnetostriction in Fe-Al and Fe-Ga alloys. Specifically, the model suggests that next nearest neighbor substitutional- substitutional pairs of tetragonal symmetry are responsible for the effect. The studies are directed to determine the model parameters self-consistently through measurements of the relaxed and unrelaxed magnetostrictive, elastic and magnetic anisotropy constants as well as lattice constants. In an effort to generalize the model the studies will be extended to Fe-C-Al and Fe-C-Ga and possibly additional alloys containing defect pairs of tetragonal symmetry. The studies will lead to a basic understanding of the significant magnetostriction in body-centered iron-base alloys. They will at minimum systematize the excess magnetostriction and maximally establish criteria for the development of novel alloys with a significant magnetostriction. %%%Materials with a magnetostriction as large as .000200 are of significant technological interest. The studies will identify the nature of the magnetostriction in body centered cubic iron base alloys and establish criteria for the search of additional magnetostrictive alloys. ***