Additive Direct-Print Fabrication of Nanocomposite Materials

ABSTRACT: The ability to fabricate arbitrarily complex insulator geometry for field-shaping purposes is an alluring property of printed plastics; however, the current generation of resins utilized in print additive-manufacturing (AM) is known to have significantly lower dielectric breakdown strength than many traditionally fabricated parts from bulk virgin plastics. In Phase I, it will be shown that by careful selection of the nanoparticle material and controlled, nanoparticle synthesis, it is possible to precisely control the size, shape, phase, and surface passivation of nanoparticles when they are produced at production-scale quantities, and it is possible to disperse them, uniformly in epoxies and polymers, without aggregation. After inkjet-printing homogeneous and heterogeneous nanocomposite discs made from various nanoparticle size, surface treatments, and volumetric densities, the dielectric constant, loss, partial discharge and breakdown voltage, and dielectric strength of the materials will be measured. Then direct inkjet deposition and powder-bed fusion methods of fabricating complexly structured high-power microwave (HPM) insulators with complex geometries, structured to minimize the electric-field stresses and capable of holding off greater than 20 kV/mm per ASTM D149, will be demonstrated.; BENEFIT: The ability to place dielectric and magneto-dielectric nanocomposites into 3D freeform structures applies low-cost, scalable additive-manufacturing (AM) techniques to enable widespread use in fabricating advanced antennas, insulators, optics, photonic circuits, and electronics for use in a wide range of consumer, automotive, and military applications.