DON26BZ01-NV034 — Effects of Additive Loading on Electromagnetic Properties in 3D Printing
Award Maximum: $140,000 (Base) / $100,000 (Option) Period of Performance: 6 months (Base) + 6 months (Option) Phase Type: Phase I
OBJECTIVE: Assess the effects of additives into 3D-printed input materials that are structurally and thermally viable for weapon system components, to determine the changes to electromagnetic (EM) properties that can be achieved based on how the additives change the material properties of 3D printed materials, and changes required to the 3D-printing process to ensure sufficient additive concentration to achieve relevant EM property changes. The end goal of this research is to establish what EM behavior effects are possible with relevant material properties for weapon systems and what additive composition are needed to obtain them. An initial use case of an antenna radome for a weapon system navigation receiver will be explored.
DESCRIPTION: Many different 3D printing techniques are currently employed today and the use of this technology has progressed from niche, one-off manufacturing to producing large components, printing directly onto complex-shaped objects, and even mass manufacture. The majority of the printing that is performed, however, focuses on pure polymer materials. There is a need to develop technologies to attenuate electromagnetic (EM) radiation for relevant purposes specific to many military applications.
Pure polymer materials traditionally used for 3D printing do not attenuate Radio Frequency (RF) and are often transparent to key frequencies. The incorporation of additives into the polymer input materials can change the EM properties of the bulk material as evidenced by initial research by the Naval Surface Warfare Center Dahlgren Division. The work in this SBIR topic is meant to determine what EM attenuation behaviors are possible with the incorporation of additives, for materials intended for use in relevant environments. This includes analyzing changes to the physical properties of the produced materials to determine how the thermal and mechanical properties as well as the printability of the materials are affected.
PHASE I: Produce additive incorporated 3D-material substrates and conducting characterization of the electromagnetic changes. (Note: The form of the materials will depend on the printing techniques employed, but could include filaments, powders, or resin materials, selected based on applicability to the expected operating environment for weapon system antenna radome.)
PHASE II: Print antenna radome representative samples with different additives and additive concentrations to assess the EM property control potential along with structural and thermal performance. Impacts to the printing process will also be assessed to determine if modifications to 3D printer software/hardware are required to reach full benefit.
PHASE III DUAL USE APPLICATIONS: Print a full-scale antenna radome prototype, with additive selection and concentration, to meet specified performance parameters for frequency transmission and rejection. Antenna radome prototypes will be characterized for EM, structural, and thermal performance prior to testing an actual weapon system. Rapid printing of prototypes using validated material specifications and printing methodologies will also be conducted to demonstrate the feasibility of in-theater replacement part manufacture with modified EM response characteristics. A dual use application would be antenna radome designs that provide a high rejection, tight bandpass to mitigate non-desired frequency interference.
KEYWORDS: Additive; Manufacturing; Electromagnetic Properties; EM; 3D Print; Nanomaterials; Transparency; Reflection; Emission