Fe-Pd-X Thin Film-Polymer Composites for Sensor Applications - First-principles evaluation of magneto-crystalline anisotropy and related intrinsic properties of Fe-Pd-X: optimization of alloy composition

用于传感器应用的 Fe-Pd-X 薄膜聚合物复合材料 - Fe-Pd-X 磁晶各向异性和相关固有特性的第一原理评估：合金成分的优化

• 批准号: 28259700
• 负责人: Privatdozent Dr. Manuel Richter
• 金额: --
• 依托单位: Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (IFW) e.V.
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/28259700?language=en
• 关键词: Fe; Pd; Thin; Film; Polymer

This project is part of a collaboration aiming at new magnetic shape memory Fe-Pd-X alloys for sensor applications. Magnetic shape memory alloys (MSMA) have received much attention in recent years. They are of interest for actuator applications due to large magnetically induced strains of up to 10% in Ni2MnGa. However, application of this material is restricted due to low blocking forces. A promising MSMA is the Fe70Pd30 alloy with smaller strains but significantly higher blocking stresses of 10 MPa. Optimization of this alloy by adding third elements is necessary to facilitate its application in sensors. Here, first-principles calculations are envisaged to (i) gain fundamental understanding of the intrinsic properties (spontaneous magnetization, tetragonal distortion, magneto-crystalline anisotropy) of Fe-Pd alloys and (ii) predict the change of intrinsic properties if other elements are added to produce ternary (quaternary) Fe-Pd-X(-Y) systems. While the field-induced strain at low external field and vanishing external stress is proportional to the spontaneous magnetization, the achievable maximum strain and the blocking stress are unavoidably determined by the magneto-crystalline anisotropy energy. Thus, knowledge of both intrinsic properties is necessary to judge the technological applicability of a certain alloy. On the other hand, the magneto-crystalline anisotropy of MSMA is difficult to measure. Thus, first-principles calculations are needed both for the prediction of expected properties and for the understanding of measured data.

该项目是针对传感器应用的新磁性内存Fe-PD-X合金的合作的一部分。近年来，磁形状记忆合金（MSMA）受到了很多关注。由于Ni2mnga中高达10％的磁性诱导菌株，它们对执行器的应用很感兴趣。但是，由于阻断力较低，该材料的应用受到限制。有希望的MSMA是FE70PD30合金，其应变较小，但封闭应力为10 MPa。通过添加第三个元素来优化该合金以促进其在传感器中的应用。在这里，将第一原理计算设想为（i）获得Fe-PD合金的内在特性（自发磁化，四方扭曲，磁晶体静脉各向异性）的基本理解，如果添加其他元素以产生ternary（quaternary）模型，则预测固有元素的变化（ii）预测固有性能的变化。虽然磁场诱导的低外侧应变和消失的外部应力与自发磁化成正比，但可实现的最大应变和阻断应力是不可避免地由磁晶状体各向异性能量确定的。因此，对于判断某种合金的技术适用性，必须了解两种内在特性。另一方面，MSMA的磁结晶各向异性很难测量。因此，对于预测性质的预测和对测量数据的理解，需要第一原理计算。