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Title: Thermographic Microstructure Monitoring in Electron Beam Additive Manufacturing

Abstract

To reduce the uncertainty of build performance in metal additive manufacturing, robust process monitoring systems that can detect imperfections and improve repeatability are desired. One of the most promising methods for in-situ monitoring is thermographic imaging. However, there is a challenge in using this technology due to the difference in surface emittance between the metal powder and solidified part being observed that affects the accuracy of the temperature data collected. This developed a method for properly calibrating temperature profiles from thermographic data and then determining important characteristics of the build through additional processing. The thermographic data was analyzed to determine the transition of material from metal powder to a solid as-printed part. A corrected temperature profile was then assembled for each point using calibrations for these surface conditions. Using this data, we calculated the thermal gradient and solid-liquid interface velocity and correlated it to microstructural variation within the part experimentally. This work shows that by using a method of process monitoring, repeatability of a build could be monitored specifically in relation to microstructure control.

Authors:
 [1];  [1];  [2];  [2];  [2];  [2];  [3]
  1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace, and Biomedical Engineering
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
  3. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace, and Biomedical Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Manufacturing Demonstration Facility (MDF)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Advanced Manufacturing Office (EE-5A)
OSTI Identifier:
1349606
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Electron Beam Melting; additive manufacturing; thermography; infrared imaging; process monitoring; microstructure

Citation Formats

Raplee, Jake B., Plotkowski, Alex J., Kirka, Michael M., Dinwiddie, Ralph Barton, Okello, Alfred O, Dehoff, Ryan R., and Babu, Sudarsanam Suresh. Thermographic Microstructure Monitoring in Electron Beam Additive Manufacturing. United States: N. p., 2017. Web. doi:10.1038/srep43554.
Raplee, Jake B., Plotkowski, Alex J., Kirka, Michael M., Dinwiddie, Ralph Barton, Okello, Alfred O, Dehoff, Ryan R., & Babu, Sudarsanam Suresh. Thermographic Microstructure Monitoring in Electron Beam Additive Manufacturing. United States. doi:10.1038/srep43554.
Raplee, Jake B., Plotkowski, Alex J., Kirka, Michael M., Dinwiddie, Ralph Barton, Okello, Alfred O, Dehoff, Ryan R., and Babu, Sudarsanam Suresh. Fri . "Thermographic Microstructure Monitoring in Electron Beam Additive Manufacturing". United States. doi:10.1038/srep43554. https://www.osti.gov/servlets/purl/1349606.
@article{osti_1349606,
title = {Thermographic Microstructure Monitoring in Electron Beam Additive Manufacturing},
author = {Raplee, Jake B. and Plotkowski, Alex J. and Kirka, Michael M. and Dinwiddie, Ralph Barton and Okello, Alfred O and Dehoff, Ryan R. and Babu, Sudarsanam Suresh},
abstractNote = {To reduce the uncertainty of build performance in metal additive manufacturing, robust process monitoring systems that can detect imperfections and improve repeatability are desired. One of the most promising methods for in-situ monitoring is thermographic imaging. However, there is a challenge in using this technology due to the difference in surface emittance between the metal powder and solidified part being observed that affects the accuracy of the temperature data collected. This developed a method for properly calibrating temperature profiles from thermographic data and then determining important characteristics of the build through additional processing. The thermographic data was analyzed to determine the transition of material from metal powder to a solid as-printed part. A corrected temperature profile was then assembled for each point using calibrations for these surface conditions. Using this data, we calculated the thermal gradient and solid-liquid interface velocity and correlated it to microstructural variation within the part experimentally. This work shows that by using a method of process monitoring, repeatability of a build could be monitored specifically in relation to microstructure control.},
doi = {10.1038/srep43554},
journal = {Scientific Reports},
number = ,
volume = 7,
place = {United States},
year = {Fri Mar 03 00:00:00 EST 2017},
month = {Fri Mar 03 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 2works
Citation information provided by
Web of Science

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