Characterization of laser energy consumption in sintering of polymer based powders

This paper presents an analysis of Laser Sintering (LS) process from an energy standpoint. LS has a potential as an environmental benign alternative to traditional processes but only few authors deal with the process optimization including the energy aspects. This work evaluates the effect of the energy density in processing of two polymeric materials: polyamide powder and a phenolic resin coated sand. The different behaviour of the two materials is studied by analysing the geometrical features (depth and width) of linear sintered structures. In particular the volumetric productivity and the energy intensity of the process are calculated to characterize the sintering process. It is shown how an upper limit to the energy consumption can be remarked. Measurements reveal that within the energy density range of 0.02-0.1 J/mm(2) the whole energy input is useful for the agglomeration process. The use of higher energy density produces different results for both the cases analysed. A proper selection of energy density maintains the energy requirement below the level of 10(6) J/kg which is considered a lower limit for manufacturing process.