Experimental investigation and numerical simulation of the stress and deformation behavior for selective laser sintering of PA6

The uneven temperature field caused by the local instantaneous heating of the laser generates the thermal stress during the selective laser sintering. The stress causes the deformation of parts, affecting the precision and mechanical properties. However, it's difficult to directly measure the stress history and deformation behavior during processing through experimental methods due to its ultra-high temperature and closed cavity. In this paper, the effects of laser power and scanning speed on the stress field and deformation of polyamide 6 by selective laser sintering were systematically investigated. The results showed that as the laser power increased or the scanning speed decreased, the z-direction stress and deformation of the specimens increased. Based on the inherent strain method, the deformation behavior of large-size parts was evaluated and in good agreement with experiments, which can guarantee the accuracy of the model and predict the deformation of parts.