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Title: Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction

Abstract

Here, we employ the high-speed synchrotron hard X-ray imaging and diffraction techniques to monitor the laser powder bed fusion (LPBF) process of Ti-6Al-4V in situ and in real time. We demonstrate that many scientifically and technologically significant phenomena in LPBF, including melt pool dynamics, powder ejection, rapid solidification, and phase transformation, can be probed with unprecedented spatial and temporal resolutions. In particular, the keyhole pore formation is experimentally revealed with high spatial and temporal resolutions. The solidification rate is quantitatively measured, and the slowly decrease in solidification rate during the relatively steady state could be a manifestation of the recalescence phenomenon. The high-speed diffraction enables a reasonable estimation of the cooling rate and phase transformation rate, and the diffusionless transformation from β to α’ phase is evident. The data present here will facilitate the understanding of dynamics and kinetics in metal LPBF process, and the experiment platform established will undoubtedly become a new paradigm for future research and development of metal additive manufacturing.

Authors:
ORCiD logo [1];  [1]; ORCiD logo [2];  [1];  [1]; ORCiD logo [3];  [2];  [1]
  1. Argonne National Lab. (ANL), Argonne, IL (United States)
  2. Carnegie Mellon Univ., Pittsburgh, PA (United States)
  3. Missouri Univ. of Science and Technology, Rolla, MO (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1374441
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; applied physics; characterization and analytical techniques; mechanical engineering

Citation Formats

Zhao, Cang, Fezzaa, Kamel, Cunningham, Ross W., Wen, Haidan, De Carlo, Francesco, Chen, Lianyi, Rollett, Anthony D., and Sun, Tao. Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction. United States: N. p., 2017. Web. doi:10.1038/s41598-017-03761-2.
Zhao, Cang, Fezzaa, Kamel, Cunningham, Ross W., Wen, Haidan, De Carlo, Francesco, Chen, Lianyi, Rollett, Anthony D., & Sun, Tao. Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction. United States. doi:10.1038/s41598-017-03761-2.
Zhao, Cang, Fezzaa, Kamel, Cunningham, Ross W., Wen, Haidan, De Carlo, Francesco, Chen, Lianyi, Rollett, Anthony D., and Sun, Tao. Thu . "Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction". United States. doi:10.1038/s41598-017-03761-2. https://www.osti.gov/servlets/purl/1374441.
@article{osti_1374441,
title = {Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction},
author = {Zhao, Cang and Fezzaa, Kamel and Cunningham, Ross W. and Wen, Haidan and De Carlo, Francesco and Chen, Lianyi and Rollett, Anthony D. and Sun, Tao},
abstractNote = {Here, we employ the high-speed synchrotron hard X-ray imaging and diffraction techniques to monitor the laser powder bed fusion (LPBF) process of Ti-6Al-4V in situ and in real time. We demonstrate that many scientifically and technologically significant phenomena in LPBF, including melt pool dynamics, powder ejection, rapid solidification, and phase transformation, can be probed with unprecedented spatial and temporal resolutions. In particular, the keyhole pore formation is experimentally revealed with high spatial and temporal resolutions. The solidification rate is quantitatively measured, and the slowly decrease in solidification rate during the relatively steady state could be a manifestation of the recalescence phenomenon. The high-speed diffraction enables a reasonable estimation of the cooling rate and phase transformation rate, and the diffusionless transformation from β to α’ phase is evident. The data present here will facilitate the understanding of dynamics and kinetics in metal LPBF process, and the experiment platform established will undoubtedly become a new paradigm for future research and development of metal additive manufacturing.},
doi = {10.1038/s41598-017-03761-2},
journal = {Scientific Reports},
number = 1,
volume = 7,
place = {United States},
year = {Thu Jun 15 00:00:00 EDT 2017},
month = {Thu Jun 15 00:00:00 EDT 2017}
}

Journal Article:
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