Nondiffractive beam shaping for enhanced optothermal control in metal additive manufacturing.
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ABSTRACT:
SUBMITTER: Tumkur TU
PROVIDER: S-EPMC8443179 | biostudies-literature | 2021 Sep
REPOSITORIES: biostudies-literature
Publications
Nondiffractive beam shaping for enhanced optothermal control in metal additive manufacturing.
Tumkur Thejaswi U TU Voisin Thomas T Shi Rongpei R Depond Philip J PJ Roehling Tien T TT Wu Sheldon S Crumb Michael F MF Roehling John D JD Guss Gabe G Khairallah Saad A SA Matthews Manyalibo J MJ
Science advances 20210915 38
High thermal gradients and complex melt pool instabilities involved in powder bed fusion–based metal additive manufacturing using focused Gaussian-shaped beams often lead to high porosity, poor morphological quality, and degraded mechanical performance. We show here that Bessel beams offer unprecedented control over the spatiotemporal evolution of the melt pool in stainless steel (SS 316L) in comparison to Gaussian beams. Notably, the nondiffractive nature of Bessel beams enables greater toleran ...[more]
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