@article {1556,
	title = {Closing the science gap in 3D metal printing},
	journal = {Science},
	volume = {368},
	year = {2020},
	pages = {583{\textendash}584},
	abstract = {<p>
	Additive manufacturing [three-dimensional (3D) printing] methodologies for high\&ndash;melting point metallic materials are being used in the advanced aerospace and biomedical sectors to fabricate high-value and geometrically complex parts in moderate production volumes. One barrier to more widespread applications is the gaps in the understanding of the processes that occur during the layer-by-layer buildup by beam heating and melting of powder or wire layers. For example, the absorption of energy in powder layers that are only a few particles thick is poorly understood. On page 660 of this issue, Khairallah et al. (1) used in situ x-ray synchrotron observations of powder dynamics coupled to thermal and hydrodynamic flow modeling to study energy absorption at the scale of powder particles. The presence of the powder, relative to a flat plate without powder, improves absorptivity at low laser power, but as power approaches 200 W, the details of the powder become far less important.
</p>
},
	doi = {10.1126/science.abb4938},
	author = {Polonsky, Andrew T. and Pollock, Tresa M.}
}
