Journal article
In situ manipulation of cooling rates during planar-flow melt spinning processing
Nano-Microstructures in Materials, Materials Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark1
Materials Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark2
Risø National Laboratory for Sustainable Energy, Technical University of Denmark3
Planar-flow melt spinning (PFMS) is a single stage rapid manufacturing/solidification technique for producing thin metallic sheet or foil. A new technology, envisioned to allow real-time manipulation of the local cooling rates and properties in melt-spun ribbon, has been tested successfully when casting Al–7%Si.
Pulsed laser heating, directed low on the upstream meniscus, or on the substrate, leaves patterns of ‘dimples’ in the ribbon. Typical cooling rates of 104 K/s have been measured using a control-volume approach. Secondary dendrite arm spacing (SDAS) has been measured through the thickness of ribbons showing areas both affected by the laser heating and unaffected by the laser.
Through a correlation of cooling rates and SDAS, it is shown that the unmodified ribbon has an average cooling rate similar to that measured macroscopically. The cooling rate underneath a laser dimple is estimated to be six times slower near the contact surface. It is envisioned that the technology described may bring the concept of ‘casting-by-design’ one step closer to realization.
Language: | English |
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Year: | 2007 |
Pages: | 172-181 |
ISSN: | 18734936 and 09215093 |
Types: | Journal article |
DOI: | 10.1016/j.msea.2006.12.123 |