Effects of surface shape on the geometry and surface topography of the melt pool in low-power density laser melting
Type
ArticleAuthors
Kim, YoungdeukKim, Wooseung
KAUST Department
Biological and Environmental Sciences and Engineering (BESE) DivisionWater Desalination and Reuse Research Center (WDRC)
Date
2011-04-15Online Publication Date
2011-04-15Print Publication Date
2012-04Permanent link to this record
http://hdl.handle.net/10754/561753
Metadata
Show full item recordAbstract
The quantitative correlations between workpiece volume and melt pool geometry, as well as the flow and thermal features of the melt pool are established. Thermocapillary convections in melt pool with a deformable free surface are investigated with respect to surface shape and laser intensity. When the contact angle between the tangent to the top surface and the vertical wall at the hot center is acute, the free surface flattens, compared with that of the initial free surface. Otherwise, the free surface forms a bowl-like shape with a deep crater and a low peripheral rim when the contact angle at the hot center is obtuse. Increasing the workpiece volume at a fixed laser intensity and a negative radial height gradient cause linear decreases in the geometric size and magnitude of flow and temperature of the melt pool. Conversely, linear increases are observed with a positive radial height gradient. © 2011 American Institute of Chemical Engineers (AIChE).Citation
Kim, Y.-D., & Kim, W.-S. (2011). Effects of surface shape on the geometry and surface topography of the melt pool in low-power density laser melting. AIChE Journal, 58(4), 998–1011. doi:10.1002/aic.12620Publisher
WileyJournal
AIChE Journalae974a485f413a2113503eed53cd6c53
10.1002/aic.12620
Scopus Count
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