Abstract Scope |
In the powder bed fusion process, exposure to oxygen and its incorporation into the melt pool is inevitable. Although oxygen exposure is conventionally recognized as a source of problems, recent experiments show otherwise, where the deliberate oxidation or introduction of oxygen actually improves the process and part quality. Hence, the influence of oxygen on the powder bed fusion process warrants further investigation. Yet, in-situ observation of the oxygen incorporation and its influence on melt pool dynamics is experimentally inexpedient, while oxygen-related effects in numerical models remain lacking. Thus, this work aims to shed light on the effect of oxygen content on melt pool dynamics through the use of thermal-fluid flow simulations. Our simulations have captured the oxygen absorption mechanism during melt pool formation and reveal its influence on the Marangoni effect and the subsequent oxygen distribution in the melt pool. The qualitative results obtained agree with experimental observations. |