Satellite Structures with Engineered or Variable Electomagnetic Properties

A novel methodology is proposed for the integration of low volume fractions (~5% by vol) of high aspect ratio ferromagnetic nanomaterials into structural composite materials, to engineer electromagnetic properties in the microwave regime. The general approach is to disperse the nanomaterial (flake form) in a thermoplastic polymer that is selected to be the same as the toughening agent in the structural thermoset resin. The flake/polymer film is then used as an interlayer between layers of structural prepreg during composite fabrication and can be positioned at specific locations within the composite, during fabrication. During composite cure, the thermoplastic dissolves into the thermoset resin, locking into place the flake dispersion and alignment characteristics. Electromagnetic properties are dependent on the flake dispersion, alignment and surface characteristics and can be engineered for absorption, reflectivity or low-loss properties. The Phase I effort will demonstrate this concept in an aerospace grade structural prepreg with Fe flakes dispersed in a sulfonated thermoplastic. Electromagnetic and mechanical properties will be characterized and models developed for property predictions.