GOALI: Collaborative Research: 3D Printed Graded-Index Magnetodielectric Devices

磁介电器件，如微波和射频透镜，是通信系统不可或缺的，例如雷达，移动，网络安全和物联网应用。与聚焦光的玻璃透镜类似，这些设备可以聚焦或以其他方式操纵无线电和微波。特别是，具有空间变化的磁性和介电性质的器件为电磁波整形提供了令人兴奋和无数的可能性，但由于缺乏实用的制造技术，仍然有待实现。喷墨印刷为制造这种器件提供了一种很有前途的方法：不同成分的油墨（例如，含有磁性和介电纳米颗粒）可以在器件的体积内以不同的比例分配，以实现所需的磁介电特性的空间梯度。这次产学研合作的目标是展示由3D喷墨打印制造的设备，这些设备具有量身定制的磁性和介电性质的空间变化，以实现给定应用所需的波形。该演示将为天线透镜等先进设备铺平道路，这些设备仅将无线电或微波信号发送到特定的WiFi设备或特定房间的周边，以减轻信号干扰或拦截的风险。该项目还将为参与的学生创造一个独特的教育和专业发展机会，他们将通过实习获得先进制造业的专业知识和行业经验，这是一个对美国具有重要经济意义的领域。此外，该项目还将与当地图书馆合作，举办旨在开展3D打印技术公共教育的讲座。这个GOALI合作项目旨在展示微波和射频磁介质器件的制造，具有专门设计的空间变化的介电常数和磁导率。该项目将结合用于电磁介质设计的变换光学技术和用于数字定向设备制造的3D喷墨打印技术。渐变折射率微波透镜天线，具有单独定制的辐射模式，将在概念验证中打印出来。该装置将以一层接一层的顺序印刷，可聚合的油墨含有高磁导率和高介电常数的介电纳米粒子。在喷射油墨时，由于粒子负载的限制，一个关键的挑战将是在印刷的复合介质中达到必要的渗透率和介电常数范围。用商业纳米颗粒配制的油墨将用于对复合材料的电磁特性进行快速调查。调查结果将指导后续定制纳米颗粒墨水的设计。油墨中纳米颗粒的大小、分散和负载将根据印刷复合材料的油墨喷射性和电磁性能范围进行优化。

Magneto-dielectric devices, such as microwave and radio frequency lenses, are indispensable to communication systems, needed for example, for radar, mobile, cyber security and internet-of-things applications. Similar to glass lenses, which focus light, these devices allow for focusing or otherwise manipulating radio and microwaves. In particular, devices with spatially varying magnetic and dielectric properties offer exciting and innumerate possibilities for electromagnetic wave shaping but remain to be realized due to lack of practical fabrication techniques. Inkjet printing provides a promising approach to manufacturing such devices: inks of different composition (e.g., containing magnetic and dielectric nanoparticles) can be dispensed in varying ratio within the volume of the device to implement the desired spatial gradient in magneto dielectric properties. The goal of this industry university collaboration is to demonstrate devices, fabricated by 3D inkjet printing, with tailor-made spatial variation in magnetic and dielectric properties to achieve wave shaping as needed by a given application. The demonstration will pave the way for advanced devices such as antenna lenses that beam radio or microwave signals only to a specific WiFi enabled machine or within the perimeter of a specific room to mitigate the risk of signal interference or interception. The project will also create a unique educational and professional development opportunity for participating students, who will acquire expertise and industry experience, via internships, in advanced manufacturing, an area of significant economic importance to the U.S. Further, in partnership with a local library, talks aimed at public education in 3D printing technologies will be presented. This collaborative GOALI project seeks to demonstrate the fabrication of microwave and radio frequency magneto-dielectric devices, with specifically designed, spatially varying electric permittivity and magnetic permeability. The project will combine transformation optics techniques for design of electromagnetic media with 3D inkjet printing for digitally directed device fabrication. Graded index microwave lens antennas, with individually customized radiation patterns, will be printed in proof of concept. The devices will be printed in a layer-by-layer sequence with polymerizable inks containing high permeability magnetic and high permittivity dielectric nanoparticles. A key challenge, due to particle loading constraints when jetting inks, will be attaining the requisite range of permeability and permittivity in the printed composite medium. Inks formulated with commercial nanoparticles will be used to conduct a rapid survey of electromagnetic properties possible in the composites. The results of the survey will guide subsequent ink design with custom nanoparticles. The size, dispersion and loading of the nanoparticles in the inks will be optimized for ink-jettability and range of electromagnetic properties achieved in the printed composites.