9457205 Orme The award is for research focused on the union of nanophase materials synthesis and net-form manufacturing with controlled molten metal droplet deposition. Novel methods of droplet generation form capillary stream break-up enable higher levels of control and manipulation of the droplet characteristics (e.g., droplet sizes and separations) than could be obtained with conventional methods of droplet generation. Precise control of the droplets trajectories (angular dispersion of the order of 1 micro- radian) is the basis for the net-form manufacturing claims. Control of the droplet sizes and trajectories leads to control of the solidification characteristics of the deposited droplets. As the droplets impinge onto a temperature controlled substrate, they "splat" and rapidly solidify. Rapid solidification leads to the synthesis of materials with refined micro/nano-structures. Preliminary experiments have demonstrated the synthesis of nanophase materials composed of low-melting point bismuthtin alloys. Technical issues to be investigated include heat transfer and phase change, fluid dynamics of droplet impact, and characterization of control parameters for optimization of net-form manufacturing and nanophase materials synthesis with higher melting-point materials. Application of novel research in droplet generation and control to the manufacturing discipline of rapid prototyping or net-form manufacturing opens the door to a novel and efficient manufacturing process that could likely increase the competitiveness of the nation's industrial base. The impact of the research is three-fold. Fist, net-form manufacturing has significant economic benefits since the engineering part is made from the raw stock in one integrated operation, thereby eliminating many machining steps. Second, noncrystalline materials synthesis is known to produce materials with enhanced mechanical and magnetic properties. Third, due to rapid solidification of the dr oplets, the synthesis of new alloys which could not be made by conventional methods due to macroscopic segregation is now a likely possibility which would have significant impact on industry and society.
