Mechanisms of selective laser sintering and heat transfer in Ti powder

Autor: N. K. Tolochko, Tahar Laoui, Ludo Froyen, Andrey V. Gusarov, M. K. Arshinov, V.I Titov
Rok vydání: 2003
Předmět:
Zdroj: Rapid Prototyping Journal. 9:314-326
ISSN: 1355-2546
DOI: 10.1108/13552540310502211
Popis: Coupled metallographic examination and heat transfer numerical simulation are applied to reveal the laser sintering mechanisms of Ti powder of 63‐315 μm particle diameter. A Nd:YAG laser beam with a diameter of 2.7‐5.3 mm and a power of 10‐100 W is focused on a bed of loose Ti powder for 10 s in vacuum. The numerical simulation indicates that a nearly hemispherical temperature front propagates from the laser spot. In the region of α‐Ti just behind the front, heat transfer is governed by thermal radiation. The balling effect, formation of melt droplets, is not observed because the temperature increases gradually and the melt appears inside initially sintered powder which resists the surface tension of the melt.
Databáze: OpenAIRE