A D V A N C E D M A T E R I A L S & P R O C E S S E S | J U L Y / A U G U S T 2 0 2 1 2 3 conclusion that it is the fluid dynamics of the melt pools and not the thermal gyrations generated by the parameters that most strongly influences the ability of gas bubbles to escape the melted material during the AM process. This difference can be attributed to the nature and morphology of the melt pools and the fluid dynamics from point-melting strategies, compared to the relatively larger and elongated melt pools that form in raster-melting strategies that contain two very distinct fluid dynamics domains, with opposing driving forces. Melt pools in point-melting strategies are almost exclusively dominated by Marangoni convection, whereas raster-melting strategies also contain a tail end to the melt pool that is dominated by drag forces. ~AM&P For more information: Peter Collins, professor, Iowa State University, 2220 Hoover Hall, 528 Bissell Rd., Ames, IA, 50011, 515.294.5127, pcollins@iastate. edu, https://www.mse.iastate.edu/ pcollins/. Acknowledgment The research is sponsored by the Department of the Navy, Office of Naval Research under ONR award number N00014-18-1-2794. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Office of Naval Research. Access to the Oak Ridge National Laboratory’s (ORNL) additive manufacturing equipment at ORNL’s Manufacturing Demonstration Facility (MDF) was facilitated by U.S. Department of Energy’s Strategic Partnership Projects (SPP) mechanism. 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