Metal-Ceramic Electromagnetostrictive Nanocomposites for Magnetoelectric Nonreciprocal Impedance Inverter

技术：在这个转型项目中，pi计划合成多功能材料（MFM），该材料(i)具有电磁致伸缩，（ii）具有磁电性，（iii）作为非互反阻抗逆变器工作，（iv）具有高机械强度。本项目将合成并研究这些新型的电控磁电（ME）纳米复合材料的结构-性能关系。利用具有磁致伸缩和导电性的金属纳米颗粒与铁磁性铁氧体形成核壳结构，实现电控ME系统。将金属铁磁核壳颗粒嵌入压电基体中并烧结在一起，形成金属-陶瓷纳米复合材料。在这种纳米复合材料中，外加电场在金属外壳中产生闭环电流，在铁氧体磁芯中产生磁场，通过磁致伸缩产生应变。这种应变通过压电相转化为电荷。电控ME纳米复合材料的合成将导致一种目前尚不存在的新型无源电网元件——旋转器的发明。结合TEM，纳米束电子衍射和x射线能量色散光谱，探针尺寸降至几纳米，将用于研究金属层在磁和压电畴结构形成中的作用。在这个项目中要回答的一个重要问题是理解纳米范围内金属层厚度对宏观ME性能的影响。通过XRD和HREM对局部ME交换进行对比研究，揭示相间界面及其取向对ME交换的影响。非技术：在这项研究和教育计划中合成的材料和器件将通过改善各种元件的性能，包括无源和有源滤波器或延迟线、磁场传感器、电流探头、只读存储器、换能器、电磁拾取器，并推进金属纳米颗粒的应用，对电子工业产生重大影响。机电材料的跨学科研究领域将吸引来自材料科学与工程、电气工程、机械工程和电子等多个专业的学生。PIs每年夏天将雇佣一名本科生从事纳米材料合成的工作。这次演习还将使他们接触到最先进的研究设施。本科学生将从工程学院选拔，并通过大学教务长提供的夏季奖学金资助。少数族裔本科生将通过西班牙裔专业工程师协会（SHPE）参与研究。项目负责人将在犹他大学秋季学期开设的“MSE 5390”铁电器件课程中开设一个实验室部分，该课程将讨论磁电材料的应用。将通过在高中举办讲座（UTA - Fort Worth Academic Connection），重点推动年轻女学生参与工程领域。将通过期刊出版物和会议记录广泛传播研究结果。PI将在美国陶瓷学会年度会议上组织“铁电和多铁材料”研讨会。应用导向的研究成果将通过每年1月最后一周举行的UTA压电系列研讨会提供给工业界。这样，这个研究和教育项目将为科学和社会做出综合贡献。

TECHNICAL: In this transformative project, PIs plan to synthesize multi-functional materials (MFM) that (i) posses electro-magnetostriction, (ii) exhibits magnetoelectricity, (iii) works as a non reciprocal impedance inverter, and (iv) displays high mechanical strength. The project will synthesize and investigate the structure-property relationship of these novel electrically controlled magneto-electric (ME) nano-composites. The electrically controlled ME system will be realized by using metal nanoparticles which are magnetostrictive and conductive forming a core-shell structure with the ferromagnetic ferrite. The metal ferromagnetic core-shell particles are embedded in a piezoelectric matrix and sintered together yielding a metal-ceramic nano-composite. In this nano-composite, the applied electric field results in a closed loop current in the metal shell inducing magnetic field in the ferrite core which generates strain through magnetostriction. This strain is converted into electric charge through the piezoelectric phase. The synthesis of the electrically controlled ME nano-composite will lead to the invention of a new passive electrical network component - gyrator - which at present does not exist. In conjunction with TEM, nano-beam electron diffraction and X-ray energy-dispersive spectroscopy with a probe size down to a few nanometers will be used to investigate the role of the metallic layer in the formation of the magnetic and piezoelectric domain structures. An important question that will be answered in this project is related to the understanding of metallic layer thickness effect in the nanometer range on the macroscopic ME properties. Comparative studies of the local ME exchange with corresponding structural investigations by XRD and HREM, will be performed to reveal how inter-phase interfaces and their orientations affect ME exchange. NON-TECHNICAL: The material and device synthesized in this research and education program will have significant impact on the electronics industry by improving performance of various components including passive and active filters or delay lines, magnetic field sensors, current probes, read-only memory device, transducers, electromagnetic pick-ups, and advance the application of metallic nanoparticles. The interdisciplinary research area of ME materials will attract students from several majors including materials science and engineering, electrical engineering, mechanical engineering, and electronics. The PIs' will hire one undergraduate student every summer to work on nano-material synthesis. This exercise will also expose them to the state-of-the-art research facilities. The undergraduate student will be drawn from the college of engineering and funded through the summer scholarships given by The Provost of the university. Minority undergraduate students will be involved in the research through the Society of Hispanic Professional Engineers (SHPE). The PI's will initiate a laboratory component to the course Ferroelectric Devices offered in the Fall Semester at UTA "MSE 5390" addressing the application of magneto-electric material. A focused effort on involvement of young women students in the engineering fields will be conducted through lectures in the high school (UTA - Fort Worth Academic Connection). Broad dissemination of the results will be achieved through journal publications, and conference proceedings. The PI's will organize the symposium "Ferroelectric and MultiFerroic Materials", at annual American Ceramic Society meeting. The application oriented results of the research will be provided to the industrial community through the UTA Piezoelectric Workshop Series which is held every year in last week of January. In this way, this research and education program will provide an integrated contribution to the science and society.