Project Details
Projekt
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
Applicant
Privatdozent Dr. Manuel Richter
Subject Area
Mechanical Properties of Metallic Materials and their Microstructural Origins
Term
from 2006 to 2009
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 28259700
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.
DFG Programme
Priority Programmes
