Some of the key factors in the success of powder bed fusion technique in additive manufacturing are the quality of powder feedstock and a uniform powder bed layer. The latter, which is essential in obtaining high-quality build part, is dictated by the powder flowability. There is evidence that steps prior to fabrication, such as shipping, may alter the flow characteristics of the powders. Considering that no significant surface chemistry change should be occurring during the transport due to minimal oxygen and moisture exposure (Ar packaging), it is likely that other factors such as triboelectric charging from frictional contact could affect the powder. In this regard, the rotating drum technique was utilized to investigate the dynamic behavior of IN625, Ti-6Al-4V and SS316L for various simulated shipping conditions. The dynamic angle and cohesive index of the powders were investigated using the GranuDrum instrument with a newly designed plastic cell avoiding charge neutralisation. Relationships correlating the charged powder behavior on spreadability will be presented.
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