Characterization of the Magnetic Distortions in Closed-Circuit Magnetic Measurements

*技术摘要*本奖项由《2009年美国复苏和再投资法案》(公法111-5)资助。1926年Weiss报道了开路测量中第一象限和第三象限磁滞回线的失真，并将其命名为镜像效应。该小组在20世纪60年代至2008年开发的闭路测量中没有报告这种失真，表明滞后失真与饱和磁化强度和铁磁样品的几何形状有关。这项研究将对变形进行研究，并对铁磁材料之间的界面相互作用有一个基本的了解。各种因素，包括铁磁试件和电磁极的饱和磁化强度和几何形状，以及施加在试件上的压力，都将被分析。将使用实际测量和计算机软件来分析铁磁材料之间的相互作用。这项研究为重温魏斯？S磁学理论的新发现提供了机会，这对于加强科学研究的基础设施和开发先进的现代技术以准确识别用于高性能可再生能源发电机/电机的新磁性材料具有重要意义。该项目为年轻科学家，例如研究生和博士后提供了一个极好的培训场所。*非技术摘要*本奖项由《2009年美国复苏和再投资法案》(公法111-5)资助。科学家和工业界都依赖于磁滞回图？在闭路测量中，用于表征被认为不存在与开路测量相关的误差的永磁材料。然而，该研究小组在2008年发表的两份报告显示，这种磁滞失真存在于闭路测量中，并与施加磁场时样品材料的磁场强度和几何形状有关。磁滞失真使识别和开发新的磁性材料变得复杂。只有全面了解这一现象，才能建立有效的纠正方法，这对于加强科学研究的基础设施和发展先进的现代技术以准确识别用于可再生能源的高性能发电机/电机的新的磁性材料是重要的。该项目将同时使用磁测量和计算机建模来研究磁滞失真，加深对这一现象的基本理解，并开发新的磁表征设备。该项目为年轻科学家，例如研究生和博士后提供了一个极好的培训场所。

***** Technical Abstract *****This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Distortion of the magnetic hysteresis loop in first and third quadrants in open-circuit measurements was reported by Weiss in 1926 and named ?image effect?. Such distortion was not reported in the closed-circuit measurements developed in 1960s until 2008 by this group, showing the hysteresis distortion to be linked with the saturation magnetization and the geometry of the ferromagnetic specimens. This research will investigate the distortion and develop a fundamental understanding of the interfacial interactions between ferromagnetic materials. Various factors, including the saturation magnetization and geometry of the ferromagnetic specimens and electromagnetic poles, as well as the pressure applied to the specimens, will be analyzed. Both actual measurements and computer software will be used to analyze the interactions between the ferromagnetic materials. This research provides a chance to revisit Weiss?s magnetic theory for new discoveries, which is important for infrastructure enhancement in scientific research and for development of advanced modern technology to accurately identify new magnetic materials for high-performance generators / motors for renewable energy. The project provides an excellent training ground for young scientists; e.g., graduate students and post-docs. ***** Non-Technical Abstract *****This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Both scientists and industry rely on magnetic ?hysteresigraphs? in closed-circuit measurements to characterize permanent magnetic materials, which are considered to be free from errors associated with open-circuit measurements. However, two reports published in 2008 by this research group show that such magnetic hysteresis distortion exist in closed-circuit measurements and is linked to the magnetic strength and geometry of the specimen materials when a magnetic field is applied. The hysteresis distortion complicates identifying and developing new magnetic materials. Only a comprehensive understanding of the phenomenon can help to establish effective correction methods, which is important for infrastructure enhancement in scientific research and for development of advanced modern technology to accurately identify new magnetic materials for high-performance generators / motors for renewable energy. This project will use both magnetic measurements and computer modeling to investigate the magnetic hysteresis distortion and develop fundamental understanding of the phenomenon, and develop new devices for magnetic characterization. The project provides an excellent training ground for young scientists; e.g., graduate students and post-docs.