FRG: New Magnetoelastic Materials with High Stress Sensitivity and Low Hysteresis

这个由爱荷华州立大学材料研究部颁发的重点研究小组奖是为了表征、理解和改进由Jiles教授和合作者发现的一种新型磁致伸缩复合材料，该材料得到了以前nsf赞助的研究（DMR-9902415）的支持。该研究的主要目的是研究理论和实验方法，通过在材料中适当的晶格位置利用原子取代方案来减少导致非线性滞后效应的交换耦合，从而提高响应线性并减少滞后。pi将探索基于金属粘合剂中的钴铁氧体的磁弹性复合材料，用于轴向和扭转非接触传感器的应力敏感材料。将制备含硅、锰和钴的钴铁氧体合金（用这些代替铁氧体中的铁），以将居里温度降低到室温，从而最大限度地减少不良的磁滞。与竞争材料相比，这些新型材料有望显著改善磁弹性特性。该奖项可以在研究生和本科阶段完成大量的研究经验，并促进教学，培训和学习。%%%拟议中的与摩拉维亚学院（一所领先的本科院校）的合作将为这两个机构拓宽经验，并可能在未来几年建立协同关系。该奖项的成功成果可能是将这些应力敏感材料用于节能和安全应用的轴向和扭转非接触式传感器的重要技术转移到许多行业

This Focused Research Group award from the Division of Materials Research to Iowa State University is to characterize, understand, and improve upon a new class of magnetostrictive composite material discovered by Professor Jiles and collaborators, who were supported by a previous NSF-sponsored research (DMR-9902415). Primary thrust of the research would be to investigate both theoretical and experimental ways to enhance response linearity and to reduce hysteresis by exploiting an atomic substitution scheme at appropriate lattice sites in the material to reduce exchange-coupling leading to nonlinear hysteretic effects. The PIs will explore magnetoelastic composites based on cobalt ferrite in a metallic binder for use as stress sensitive materials in axial and torsional non-contact sensors. Alloys of cobalt ferrite with Silicon, Manganese and Cobalt (substituting these for the Iron in the ferrite) will be prepared to reduce the Curie temperature to room temperature thereby minimizing undesirable hysteresis. These new class of materials are expected to significantly improve magnetoelastic characteristics over competitive materials. %%%This award could accomplish substantial research experience combined with promotion of teaching, training, and learning both at the graduate and undergraduate levels. The proposed collaboration with Moravian College, a leading undergraduate institution would be a broadening experience for both institutions and will likely create a synergistic relationship for years to come. A successful outcome of this award could be a significant technology transfer to a number of industries in the use of these stress sensitive materials in axial and torsional non-contact sensors in energy conservation and safety applications