Adsorbed water films can also have a negative impact on powder flow and effective density of the powder beds [4, 7, 8].
Hydroxides and hydrated oxides
Impact on process repeatability
Humidity and temperature variations might be too small to affect powder flow, melting and solidification mechanisms and final properties of additively manufactured parts. Or they could turn out to be critical.
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 Rainer J. Hebert, Viewpoint: metallurgical aspects of powder bed metal additive Manufacturing, J Mater Sci, 5 October 2015 - DOI 10.1007/s10853-015-9479-x
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