Experimental and Numerical Study on the Flow of Fine Powders from Small-Scale Hoppers Applied to SLS Multi-Material Deposition-Part I

We present experimental guidelines for the delivery of powders under 100µm through hopper-nozzle orifice diameters on the order of 1mm. Small-scale hoppers will be incorporated into an SLS powder deposition system for creating thin layers of multiple powdered materials in a patterned bed. This is a preliminary investigation on the flow behavior for selected orifice diameters and particle sizes under gravity or low pressure-assisted flow conditions. A method for numerically modeling the gas-particle behavior in hopper-nozzles is presented and conditions for achieving continuous mass flow rates are demonstrated.