Performance Improvements of Additive Manufactured RF Antennas and Waveguides

Metal additive manufacturing has demonstrated significant cost and schedule savings with exceptional ability in producing a geometrically complex monolithic part that is unattainable or extremely difficult and costly to produce through conventional manufacturing. The basic building blocks for RF antennas and waveguides are sophisticated, convoluted internal cavities and passages that is particularly suited for AM 3D printing. However, the additively produced metallic thin wall structure doesn’t have the surface finish quality and refined dimension accuracy as traditional assembled structures. Even through additive manufactured RF antennas and wave guides provided low cost pathway for volume production, there are still performance gaps compared to conventional manufactured RF antennas. In this proposed work, Castheon, Inc. a premier US additive manufacturing research & development company and Rantec Microwave Systems, a leader in FR antenna industry for over 60 years, a fully integrated design, manufacturing, and testing RF turnkey system and antenna subsystem provider, are joining forces in pursuing significant quality improvement in the additive manufactured RF antenna and waveguides. This will be accomplished by conducting focused characterization of additive manufactured RF antennas, waveguides, and connectors in two commonly used materials, aluminum and copper alloy. In this effort, RF performance against material defects (voids) and their distribution in the subsurface and the bulk will be evaluated in addition to the surface finish quality and refined dimension accuracy’s impact on RF performance. Our primary focus on RF system materials are an enhanced AlSi10Mg alloy which offers equivalent of 6016-T6 properties and copper alloy C18150, a high conductivity Cr Zr strengthened alloy. Castheon also developed high quality, high productivity 7075 equivalent high strength aluminum (7A77) and higher conductivity unalloyed copper material, these materials can be substitute to our primary focused alloys at MDA program manager’s disposal Castheon is also developing and maturing a novel NDE process that is a high energy and high-resolution DR/CT scanning with the GLO Transparent Ceramic Scintillator. This high throughput NDE process along with Rantec’s in house X ray inspection process will be applied to characterize the RF antenna and waveguide’s materials integrity and structural compliance. As a fully integrated design, manufacturing, and testing RF turnkey system provider, Rantec has full-fledged in-house conventional manufacturing processes including dip brazing, precision machining, and assembly capability. Additionally, Rantec also has in house inspection including X-ray and RF testing capability. All these capable assets will be available supporting this effort if awarded for full RF performance characterization and comparison between conventionally manufactured RF antenna, waveguide, and connector, and additively manufactured counterpart. Approved for Public Release | 20-MDA-10643 (3 Dec 20)