A concept for multi-material solid freeform fabrication is proposed to enable the fabrication of
heterogeneous components. This concept features nozzles designed for depositing thin layers of multiple
patterned materials followed by selective laser sintering for consolidation to desired densities. Although
prior work on the design of small-scale nozzles for powder delivery is lacking, our design is guided by
background theory for particle flow through hoppers. Experimental guidelines for the delivery of powders
with particle sizes in the 10-125µm range through hopper-nozzle orifices with diameters in the 0.5-2mm
range are presented. This is a preliminary investigation of particle flow behavior necessary for continuous
mass flow rates under gravity, low gas pressure-assisted flow, and vibration-assisted flow conditions. As
proof of concept, several patterned beds of single and multiple materials were deposited on an X-Y table.
A simple model to predict the linewidth of lines deposited by gravity flow is presented.Mechanical Engineerin
