Micro-foamed structural materials for micro-aircraft

Abstract The development of micro-air vehicles poses a considerable challenge to the materials scientist. Vehicles that may occupy less than 10cm in any direction require many structural components with dimensions well below 1mm when conventional engineering and assembly techniques are employed. As with conventional unmanned air vehicles (UAVs), and full-scale aircraft, materials that display a huge breadth of characteristics are required to build the airframe and to engineer sub-components, while meeting stringent mass and volume budgets. In particular, high modulus, high toughness, easy formability and jointing are desirable qualities. For larger structures, conventional foamed materials can meet some of these properties. However, the pore sizes in these conventional materials are too large to allow manufacture of micro-scale components, airframe sections and skins. This paper describes the manufacture and properties of some micro-foamed polymers, and polymer composites, metals and oxide ceramics that are being developed at DERA specifically for micro-vehicle applications.