Influence of hatch spacing and laser spot overlapping on heat transfer during laser powder bed fusion of aluminum alloy

Direct metal laser sintering is a kind of laser powder bed fusion process that emerged as an advanced manufacturing process in the recent era of industry 4.0. This is a rapid manufacturing process where repeated melting and solidification takes place during scanning of the powder bed. The characteristics of the as-built component depend on the melting and solidification behavior which is directly influenced by the processing conditions. Intending to make a superior part in this process, it is indispensable to comprehend the impact of process parameters on temperature distribution, melting and solidification behavior, etc. In the present study, the authors developed an improved three-dimensional transient heat transfer model and studied the influence of hatching space and laser spot overlapping on temperature distribution with molten pool behavior on the AlSi10Mg powder bed. From this investigation, it was observed that the temperature on the AlSi10Mg powder bed decreases with an increase in hatch spaces and conversely with increasing the laser spot overlapping the temperature increases. Also, the molten pool dimension changes with variation of hatch spacing and laser spot overlapping. By combining these studies, the manufactures can able to optimize the hatch space and laser spot overlap along with other processing parameters to fabricate quality components.