Freeform Fabrication of Refractory Metal Absorber/Thruster Components

The proposed work addresses the generic need for more flexible methods of fabricating complex-shaped, three demensional solid objects from refractory structural materials. The proposed technology will enable fabrication of complex-shaped refractory metal components which cannot be made using existing techniques. As an example, honeycomb structures and tube bundles can be fabricated in which the cross section and shape of each individual tube or cell is varied at will. The Phase I effort will focus on tungsten because of its broad application in a variety of industrial and Government sectors including absorber/thruster systems for solar thermal propulsion. The objectives of the Phase I effort are to demonstrate mechanical prooperty feasibility in flat test speciments, to determine dimensional accuracy and resolution and to demonstrate some of the virtually unlimited shape intricacy capaability of the process.