射频与微波等磁介低温共烧电子陶瓷材料研究

Electroceramic materials with equivalent magnetic permeability and dielectric permittivity (equivalent permeability and permittivity) have become the academic hot point of the materials research around the world. This kind of materials are the basis of the high efficient, broadband, and small scaled microwave devices for the mobile telecommunications. Firstly, we will establish the theoretical models of the ferromagnetic resonance and electrical domain resonance for the ferrous magnetic materials; then provide the frequency dependent permeability and permittivity curves of the materials with equivalent permeability and permittivity. Its equivalent condition will be also provided. Secondly, we will propose the theoretical model of the low temperature firing electroceramic materials with equivalent permeability and permittivity. The relationship among loss, frequency, composition, and processing will also be provided. Thirdly, three different sets of materials with equivalent permeability and permittivity will be developed. The first set of material system is the spinel structured micron-scaled NiZn combined with nano-scaled BaTiO3 composite applied for the frequency range of 3-100 MHz. The second set is the micron-scaled hexagonal Co2Z ceramics doped with SnO2 nano-powders applied for the frequency range of 300-1200 MHz. The third set is the microwave gyromagnetic LiZn ferrites applied for the frequency range of 2-18 GHz. In the end, we will explore the effect of the doping amount on the density, microstructure, and magnetic-dielectric performance; then design and produce antenna devices based on the materials we developed, which in turn, will also validate the effectiveness of the materials.

具有相等磁导率和介电常数的电子陶瓷材料（等磁介）不仅成为国际材料界研究的热点科学问题，而且为移动通信中高效、宽带、小尺度微波器件打下材料基础。项目首先建立亚铁磁体磁畴共振与电畴共振理论模型，给出等磁介材料磁导率和介电常数频谱曲线及两者相等的条件；其次，提出等磁介电子陶瓷材料的低温共烧结理论模型，找到等磁介和双低损耗与频域、配方、工艺之间的理论和实验相关性；再者，研制出三类等磁介电子陶瓷材料：第一类是微米尖晶石NiZn与纳米BaTiO3进行复合形成3-100 MHz频段等磁介材料，第二类是微米六角铁氧体Co2Z中掺杂纳米SnO2陶瓷形成300--1200 MHz 频段等磁介材料；第三类是微波旋磁LiZn铁氧体掺杂BBSZ玻璃陶瓷形成微波段2—18GHz 频率范围等磁介材料；最后，探究掺杂量的多少对材料的致密度，微观形貌和磁介性能的影响，设计制作不同频域的天线器件对合成新材料进行验证。

本项目按照研究计划，通过固相反应法等方法分阶段制备了不同配方的等磁介铁氧体及微波陶瓷材料，通过调整材料配方及制备工艺等手段获得了具有不同性能的等磁介材料；通过XRD衍射技术、SEM表观形貌分析、磁谱与介电谱技术等实验手段，分别获取了不同配方材料的微观结构及磁电性能变化规律；分析了配方种类、掺杂离子类型、实验工艺对材料微观结构、磁性能、介电性能的影响规律，找到了等磁介和双低损耗与频域、配方、工艺之间的理论和实验相关性，建立了亚铁磁体磁畴共振与电畴共振理论模型，给出了等磁介材料磁导率和介电常数频谱曲线及两者相等的条件。基于研发的等磁介材料体系和天线理论，利用ANSYS Electromagnetics Suit软件设计并仿真了工作于VHF波段的微带圆极化贴片天线，经过尺寸优化，制作得到了带宽较宽、圆极化性能良好的微带天线，设计并制作了不同频域的天线器件对合成新材料进行了验证。项目实际执行情况良好。