Investigation of the Lithium-Containing Aluminum Copper Alloy (AA2099) for the Laser Powder Bed Fusion Process [L-PBF]: Effects of Process Parameters on Cracks, Porosity, and Microhardness

In order to widen the alloy spectrum for the laser powder bed fusion process, apart from the popular Al-Si-based alloys, AlSi10Mg and AlSi12, the precipitation-hardenable AA2099 wrought alloy has been considered in this work. The effect of varied laser power, scanning speed, a preheated base plate (in situ heat treatment) and post-heat treatments on porosity, cracks and microhardness was observed. The results indicate a successfully printed crack-free part with very minimal porosity at 90W laser power and 550mm/s scanning speed with microhardness of 72 HV0,1 at a 520 degrees C preheat treatment temperature. The influence of added titanium aluminide powder in crack removal and grain refinement is also reported in this work.