Metal-Ceramic Electromagnetostrictive Nanocomposites for Magnetoelectric Nonreciprocal Impedance Inverter

技术：在这个变革性的项目中，PI计划合成多功能材料(MFM)，这种材料(I)具有电磁伸缩，(Ii)具有磁电性，(Iii)作为非互易阻抗反相器工作，(Iv)表现出高机械强度。该项目将合成并研究这些新型电控磁电(ME)纳米复合材料的结构-性能关系。利用磁致伸缩导电的金属纳米粒子与铁磁性铁氧体形成核壳结构，实现电控微电子系统。将金属铁磁性核壳颗粒埋入压电体中，并烧结在一起，得到金属-陶瓷纳米复合材料。在这种纳米复合材料中，外加电场在金属壳层中产生闭环电流，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新的无源网络元件-回转器的发明-目前还不存在。结合透射电子显微镜、纳米束电子衍射和X射线能谱分析，我们将研究金属层在磁性和压电域结构形成过程中的作用。在这个项目中要回答的一个重要问题是了解纳米范围内金属层厚度对宏观ME性质的影响。我们将用X射线衍射仪和高分辨电子显微镜对局部ME交换进行对比研究，以揭示相间界面及其取向对ME交换的影响。非技术性：这项研究和教育计划中合成的材料和器件将通过提高各种元件的性能，包括无源和有源滤波器或延迟线、磁场传感器、电流探头、只读存储器件、换能器、电磁拾取器，并促进金属纳米颗粒的应用，对电子行业产生重大影响。ME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、机械工程和电子等几个专业的学生。PIS将在每年夏天雇佣一名本科生从事纳米材料合成工作。这次演习还将使他们接触到最先进的研究设施。本科生将从工程学院中挑选出来，并通过大学教务长提供的暑期奖学金提供资金。少数族裔本科生将通过西班牙裔专业工程师协会(SHPE)参与这项研究。PI‘s将在UTA“MSE 5390”秋季学期开设铁电器件课程的一个实验室组件，介绍磁电材料的应用。将通过在高中的讲座(UTA-Fort Worth学术联系)，重点努力让年轻女学生参与工程领域的工作。将通过期刊出版物和会议记录广泛传播成果。国际陶瓷协会将在美国陶瓷学会的年度会议上组织“铁电和多铁材料”研讨会。面向应用的研究成果将通过每年1月最后一周举行的UTA压电研讨会系列提供给工业界。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.