The Influence of Powder Reuse on the Properties of Nickel Super Alloy ATI 718™ in Laser Powder Bed Fusion Additive Manufacturing

Gas-atomized nickel alloy ATI 718™ powders with a nominal particle distribution of 15 to 45 µm were used in a laser powder bed fusion (LPBF) additive manufacturing (AM) process for ten sequential builds without refreshing with new powder. The repeated feedstock use caused the particle size distribution, particle morphology, and oxygen content to change in comparison to virgin powder. Unusual particle morphologies were observed in the powder with repeated use when compared to virgin gas-atomized feedstock. Particles after use were found to contain surface features such as films and spots, which consisted of aluminum oxides and likely contributed to increasing the oxygen content in the recycled feedstock powder.