In this proposed Phase I program, a multifunctional lightweight radiation shield composite will be developed and fabricated. This structural radiation shielding will be a high strength, syntactic polymeric where the polymer is filled with high strength low Z material. Specifically, this program will produce structural Polymeric aluminum alloy-LiBH4 composite materials layups. These structural composites are derived from similar structures Powdermet currently produces using hollow spheres (lightweight insulating structures), and more recently, energetic materials (such as KClO4). These materials serve to provide combined structural properties, thermal insulation, mass-efficient radiation shielding, and collision and micrometeroid impact energy adsorption.