Multifunctional graded dielectrics fabricated using dry powder printing

作者：Good Austin J^*; Roper David; Good Brandon; Yarlagadda Shridhar; Mirotznik Mark S

来源：Smart Materials and Structures, 2017, 26(9): 095036.

DOI：10.1088/1361-665X/aa782b

• additive manufacturing
• composites
• dielectrics
• effective medium approximation
• microstrip filters
• modeling
• beamforming

The ability to fabricate multifunctional devices that combine good structural properties with embedded electromagnetic functionality has many practical applications, including antireflective surfaces for structural radomes, load bearing conformal antennas, integrated RF transmission lines and passive beam forming networks. We describe here a custom made 3D printer that can print high dielectric constant ceramic powders within a low-loss structural composite substrate to produce mechanically robust parts with integrated graded dielectric properties. We fabricated a number of these parts and evaluated their anisotropic dielectric properties by determining the complete permittivity tensor of the printed samples as a function of local powder weight. This data was then experimentally validated using two practical examples: a Chebyshev antireflective stack and a 2D passive beamsteering network. The results of both electromagnetic systems displayed acceptable agreement between the simulated and measured results. This agreement shows that powder printing is a potential approach for fabricating spatially graded dielectric electromagnetic systems.

• 出版日期2017-9