Abonnement à la biblothèque: Guest
Portail numérique Bibliothèque numérique eBooks Revues Références et comptes rendus Collections
Atomization and Sprays
Facteur d'impact: 1.737 Facteur d'impact sur 5 ans: 1.518 SJR: 0.814 SNIP: 1.18 CiteScore™: 2.2

ISSN Imprimer: 1044-5110
ISSN En ligne: 1936-2684

Volumes:
Volume 30, 2020 Volume 29, 2019 Volume 28, 2018 Volume 27, 2017 Volume 26, 2016 Volume 25, 2015 Volume 24, 2014 Volume 23, 2013 Volume 22, 2012 Volume 21, 2011 Volume 20, 2010 Volume 19, 2009 Volume 18, 2008 Volume 17, 2007 Volume 16, 2006 Volume 15, 2005 Volume 14, 2004 Volume 13, 2003 Volume 12, 2002 Volume 11, 2001 Volume 10, 2000 Volume 9, 1999 Volume 8, 1998 Volume 7, 1997 Volume 6, 1996 Volume 5, 1995 Volume 4, 1994 Volume 3, 1993 Volume 2, 1992 Volume 1, 1991

Atomization and Sprays

DOI: 10.1615/AtomizSpr.2012005918
pages 581-601

VACUUM-ASSISTED GAS ATOMIZATION OF LIQUID METAL

Steven P. Mates
National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
S. D. Ridder
National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
F. S. Biancaniello
National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
T. Zahrah
MATSYS, Inc., Sterling, VA, 20166, USA

RÉSUMÉ

Vacuum-assisted gas atomization of liquid metal is explored. The investigation is motivated by observations of liquid metal atomization that indicate that secondary atomization is sustained over an extended distance from the nozzle tip. Increasing the velocity of the gas flow downstream of the nozzle exit by lowering the nozzle back pressure below ambient may therefore improve atomization efficiency. Supersonic jets grow in length when the nozzle back pressure is lowered due to an increase in the nozzle pressure ratio. However, since the nozzle mass flux remains fixed, any improvements in vacuum-assisted atomization efficiency will be realized without any increase to the gas-to-metal mass flow ratio, which is of interest both academically and practically as gas consumption can be costly. Small (25-kg batch) atomization runs were performed using an Al-Cu-Ni glass-forming alloy in which a high-mass-flow vacuum system was employed to maintain a sub-ambient chamber pressure over the course of an entire run. The powder produced in this manner was then compared to the conventional method without the vacuum system operating. Results demonstrate that atomizing into a partial vacuum decreases the frequency of the coarsest particles in the powder size distributions, leading to a narrower particle size distribution. Further, they underscore the importance of the axial length scale affecting secondary atomization that is related to, but not fully described by, the gas-to-liquid mass flux ratio. The present experiments point out a significant and unexplored parameter space that may be exploited to increase control over particle size distributions.


Articles with similar content:

EFFERVESCENT ATOMIZER OPERATION AND SPRAY CHARACTERISTICS
Atomization and Sprays, Vol.3, 1993, issue 2
J. D. Whitlow, Arthur H. Lefebvre
EFFERVESCENT ATOMIZATION OF HIGH-VISCOSITY FLUIDS: PART I. NEWTONIAN LIQUIDS
Atomization and Sprays, Vol.1, 1991, issue 3
Paul E. Sojka, Harry N. Buckner
A STUDY OF LIQUID METAL ATOMIZATION USING CLOSE-COUPLED NOZZLES, PART 1: GAS DYNAMIC BEHAVIOR
Atomization and Sprays, Vol.15, 2005, issue 1
Steven P. Mates, Gary S. Settles
THE PERFORMANCE CHARACTERISTICS OF SOLID-CONE-SPRAY PRESSURE-SWIRL ATOMIZERS
Atomization and Sprays, Vol.10, 2000, issue 6
D. D. James, J. R. Jeong, R. A. Sharief
SIMULTANEOUS MEASUREMENT FOR COMPARISON OF DROPLET SIZES MEASURED BY FREEZING METHOD WITH THOSE BY LASER LIGHT SCATTER DETECTION METHODS
ICLASS 94
Proceedings of the Sixth International Conference on Liquid Atomization and Spray Systems, Vol.0, 1994, issue
Toshio Kurabayashi, T. Nagasaka, Siichi Shiga, K. Kawabata, Takao Karasawa