GOALI: Nanocrystalline Oxides For Integrated, Soft Magnetic Applications

该计划的科学目标是学习如何操纵纳米晶颗粒之间的磁耦合，以创建软磁材料，其中的体磁特性，如场的磁导率，磁化强度和矫顽力损耗可以独立变化。在整体材料中，这些性质不是独立的。 所采取的方法是合成纳米晶磁性氧化物颗粒，并将其填充到块状材料中，以通过组成、粒度、形状和体积分数来改变颗粒间的磁耦合。 最初，铁氧体和稀土氧化物的纳米颗粒是使用反胶束工艺合成的，并且它们的间距和堆积通过选择表面活性剂和溶剂而变化，以形成与电力转换器和相关设备中的使用相容的散装材料。该材料的特点是在不同的阶段，以确定块体磁性能是如何相关的纳米晶颗粒的性质和他们的磁coupled.The总体理由的程序是评估潜在的纳米晶基材料在取代现有的磁性材料在直流-直流电力转换器，通过提高他们的性能和降低他们的物理尺寸。电源转换器在整个电子工业中使用，为几乎全数字电子设备和微处理器提供稳定的低压电源。 对更小、更高功率、更高频率的dc-dc转换器的日益增长的需求只能通过具有改善的磁导率和更低的磁损耗的磁性材料的开发来实现。正在解决的挑战是如何使用纳米晶颗粒制造新的磁性材料，这些材料可以制造成集成的功能性功率转换器，同时保持其新颖的磁性组合。 与罗克韦尔科学公司的合作为学生提供了在功率器件的磁性元件的设计经验，以及测试他们的候选材料，因为他们正在开发的机会。

The scientific goal of the program is to learn how to manipulate the magnetic coupling between nanocrystalline particles to create soft magnetic materials in which the bulk magnetic properties, such as permeability in field, magnetization and coercive losses can be independently varied. In monolithic materials these properties are not independent. The approach being taken is to synthesize nanocrystalline magnetic oxide particles and manipulate their packing into a bulk material to alter, through composition, particle size, shape and volume fraction, the inter-particle magnetic coupling. Initially, nano-particles of ferrites and rare-earth oxides are being synthesized using inverse micelle processes and their spacing and packing varied through the choice of surfactants and solvents to form bulk material compatible with use in electrical power converters and related devices. The materials are characterized at different stages to determine how the bulk magnetic properties are related to the properties of the nanocrystalline particles and their magnetic coupling.The overall justification of the program is to assess the potential for nanocrystalline-based materials in replacing existing magnetic materials in dc-dc electrical power converters by enhancing their performance and decreasing their physical size. Power converters are used throughout the electronics industry to provide a stable, low voltage power supply to almost all-digital electronics and microprocessors. Increasing demands for smaller, higher power, higher frequency dc-dc converters can only be realized with the development of magnetic materials having improved permeability and lower magnetic losses. The challenge being addressed is how to create new magnetic materials, using nanocrystalline particles, which can be fabricated into an integrated and functional power-converter whilst preserving their novel combination of magnetic properties. The collaboration with Rockwell Scientific Company provides students with experience in the design of the magnetic components of power devices as well as the opportunity to test their candidate materials as they are being developed.