Simulation based two level factorial designed experiments for optimisation of selective laser sintering process

In this paper, a methodology has been presented to optimise the process parameters for selective laser sintering (SLS) process using the finite element method (FEM) based simulation and design of experiments (DOE). A systematic DOE was performed using 23 full factorial designs to first establish the different simulation experiments that were needed to be carried out. The simulation experiments were then implemented in the Ansys®, APDL™ environment to determine the evolution temperature distribution and density variation with time in the SLS of bisphenol-A polycarbonate. The results of the simulation in terms of the average density were regressed and subjected to ANOVA to identify the important process parameters affecting the final density of the laser sintered part and the relationship between them. DesignEase® software was used to analyse the designed experiments. Laser power and scan spacing were found to be significant parameters affecting the part density. Amongst the interaction terms, significant effect of laser power was found on the part density at the lower settings of the scan velocity. At the higher setting of scan velocity the density was almost constant.