Selective Infrared Sintering of Polymeric Powders using Radiant IR Heating & Ink Jet Printing

Established methods of rapid prototyping by sintering polymeric powders have predominantly focused on the use of lasers to selectively heat the polymeric particles together to form fused layers. Although effective, this route requires the laser to draw in the entire cross section of the slice and this limits the speed of the process, particularly for the production of thick walled parts. The use of IR radiant lamps to fuse an entire layer simultaneously has been explored by several groups and is now the basis of at least one commercially available process (Speed Part). An alternative route, developed by the Rapid Prototyping & Manufacturing Group (RPMG) at DeMonfort University, where areas of the powder bed are selectively treated to promote absorption by particular IR radiation will be described in this paper. The advantages of this approach and the limitations which must be overcome through further research will be fully discussed.