Predicting the element loss in aluminum (AA2195) powder produced by gas atomization with a numerical model

Abstract

Gas atomization (GA) is commonly used for making metal powders for additive manufacturing due to its efficiency and cost-effectiveness. However, the process results in the loss of low-boiling temperature elements like magnesium and lithium. These can negatively impact the performance of lightweight components of AA2195. To understand and address this issue, we used Inductively Coupled Plasma to compare the composition of ingots and powders produced by GA. The results showed a loss of around 20% of magnesium and lithium during the process. To investigated this symptom scientifically, we developed a numerical model based on evaporation theory. The simulation findings indicated that the loss of elements took place nearby the nozzle. Furthermore, it was observed that the utilization of powder with larger particle sizes resulted in a higher degree of element loss. Based on the results of simulation, we optimized the GA parameters and produced new powders that meet design criteria.