Research output: Contribution in Book/Report/Proceedings - With ISBN/ISSN › Conference contribution/Paper › peer-review
Publication date | 2012 |
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Host publication | Innovative Developments in Virtual and Physical Prototyping |
Editors | PJ Bartolo, ACS DeLemos, APO Tojeira, AMH Pereira, AJ Mateus, ALA Mendes, C DosSantos, DMF Freitas, HM Bartolo, HD Almeida, DosReis IM, JR Dias, MAN Domingos, NMF Alves, RFB Pereira, TMF Patricio, TMD Ferreira |
Place of Publication | Boca Raton |
Publisher | CRC PRESS-TAYLOR & FRANCIS GROUP |
Pages | 625-633 |
Number of pages | 9 |
ISBN (print) | 978-0-415-68418-7 |
<mark>Original language</mark> | English |
Event | 5th International Conference on Advanced Research and Rapid Prototyping - Leiria Duration: 28/09/2011 → 1/10/2011 |
Conference | 5th International Conference on Advanced Research and Rapid Prototyping |
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City | Leiria |
Period | 28/09/11 → 1/10/11 |
Conference | 5th International Conference on Advanced Research and Rapid Prototyping |
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City | Leiria |
Period | 28/09/11 → 1/10/11 |
This research presents a comparative study of the characteristics of laser additive manufacturing (LAM) using two types of Ti-6A1-4V powder. Ti-6A1-4V powders prepared using the gas-atomization (GA) and the plasma rotating electrode (PREP) processes were first analyzed using laser diffraction, scanning electron microscopy and microcomputed tomography. A 1.5 kW diode laser with a coaxial deposition head was then used to deposit a number of thin-wall structures at a range of processing parameters from each of the powders. The deposited structures were characterized using optical microscopy, scanning electron microscopy, x-ray diffraction and microcomputed tomography (MicroCT). In both cases, deposits of Ti-6A1-4V exhibit a unique epitaxial prior beta grains microstructure that transforms to alpha lathes and retained beta during cooling. X-ray diffraction results show that the overall microstructure is alpha + beta. The lamellar alpha + beta phase spacing (S alpha+beta) increases with laser power but seems unaffected by variation in the powder mass flow rate. Micro hardness of the laser deposited Ti-6A1-4V is dependent on the lamellar a 0 phase spacing (S alpha+beta). The results show some potential benefits of using PREP powder in laser additive manufacturing. PREP powder has a higher deposition rate and deposits show lower intralayer porosity and lower surface roughness. However, PREP powder deposits show lower micro hardness than GA powder deposits.