Density prediction of crystalline polymer sintered parts at various powder bed temperatures

The effect of powder bed temperature setting on the prediction of density of sintered parts produced by the selective laser sintering (SLS) process is reported. A crystalline polymer, nylon-12 - commercially named Duraform polyamide - has been used in this work. To study the effect of the powder bed temperature, a two-dimensional model of the sintering process for crystalline polymers has been developed. Latent heat has been considered in the model. Three powder bed temperature settings, 174, 178 and 182 degreesC, have been applied to study their effect on the sintered parts' density and size accuracy. This paper only reports on density. Results show that at a powder bed temperature of 182 degreesC, a fully solid density, 970kg/m(3), can be obtained at a default energy density of 0.0284J/mm(2). By reducing powder bed temperature to 178 degreesC, at the same energy density, density of a sintered part decreases by about 4 per cent.