DOE based three-dimensional finite element analysis for predicting density of a laser-sintered part

Purpose The purpose of this paper is to investigate the transient three-dimensional temperature distribution for a laser sintered duraform fine polyamide part by a moving Gaussian laser beam. The primary objective of the present paper is to develop computationally efficient numerical simulation technique with the commercially available finite element software domain for the accurate prediction of the temperature history and heat-affected zones of the laser sintered parts so as to finally obtain the density of the sintered sample. Design/methodology/approach The paper proposes a mathematical model of scanning by moving laser beam and sintering sub-model. Based on the mathematical models, a simulation model was developed by using author written subroutines in ANSYS (R) 11.0, a general purpose finite element software. The simulation model was then run at experimental designed points using two-level factorial design of experiments (DOE) approach. The data thus generated were used to predict the equation for the density of sintered part in terms of process parameters using Design Expert software in order to analyse the designed experiments. Findings 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. Temperature-time plots were generated to study the transient temperature distribution for the sintering process and with further applicability to study the thermal stresses. Research limitations/implications The simulation model hence developed can be used for only simple part geometries and cannot be generalised for any complex geometry. Originality/value The paper presents a simulation model which is integrated with a DOE approach so as to develop a robust as well as simple and fast approach for the optimization of quality objective.