The objective of the present work is to develop a fundamental knowledge base for microscale dropwise melt deposition, and to explore possible applications and equipment design for those applications. A variety of modes of controlled microdrop deposition will be investigated, followed by detailed quantitative studies aimed at identifying the controlling thermo-physical processes and the parameters that determine satisfactory deposition in each mode. These studies will be made using microdrops of various waxes in a test system which is capable of generating very reproducible droplets at various melt temperatures and droplet deposition speeds over a broad range of deposition frequencies. Although these investigations use waxes, one of the main objectives of the program will be to develop scaling laws for the various deposition modes, and possibly also some useful analytical models based on simplified models of the thermo-physical solidification processes that are involved. This will lead to an understanding of how the data for wax extrapolates to other melt materials. Some tests will also be made with low melting point metals like tin as a check on the proposed scaling laws derived from analysis and data on waves. The buildup of materials or physical objects by controlled deposition of melt microdrops has potential applications in rapid prototyping, 3D copying, direct fabrication of small structures including electronics packaging and materials processing.
