Analysis of the phase transformation of AlSi10Mg during Laser Powder Bed Fusion

Abstract The characteristics of the process zone during Laser Powder Bed Fusion (LPBF) are decisive for the quality of additively manufactured parts. Thermographic measurements give an insight into the temperatures of the melt pool and its surroundings. Particularities in the temperature field can be attributed to the process dynamics or the alteration of the alloy composition during LPBF. This study presents a method for the analysis of the phase transformation during the process. It is demonstrated that thermographic measurements allow a detailed investigation of the liquidus and the solidus temperature. Experiments with AlSi10Mg revealed a direct interaction between the energy input and the resulting constitutional undercooling. Based on this finding, process parameters can be adjusted during LPBF to control the phase transformation process of the alloy.