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Title: Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy

Abstract

Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain, texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. Additionally, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.

Authors:
 [1];  [2];  [2];  [3];  [4]
  1. Univ. of California, Berkeley, CA (United States)
  2. General Electric Global Research Center, Niskayuna, NY (United States)
  3. Consiglio Nazionale delle Ricerche, Instituto Sistemi Complessi (CNR-ISC), Sesto Fiorentino (Fl) (Italy)
  4. Japan Atomic Energy Agency, Naka-gun Ibaraki (Japan)
Publication Date:
Research Org.:
NOVA Scientific, Inc., Sturbridge, MA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1313815
Grant/Contract Number:
FG02-07ER86322; SC0009657
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Science and Technology of Advanced Materials
Additional Journal Information:
Journal Volume: 17; Journal Issue: 1; Journal ID: ISSN 1468-6996
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; non-destructive testing; additive manufacturing; microstructure; neutron imaging

Citation Formats

Tremsin, Anton S., Gao, Yan, Dial, Laura C., Grazzi, Francesco, and Shinohara, Takenao. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy. United States: N. p., 2016. Web. doi:10.1080/14686996.2016.1190261.
Tremsin, Anton S., Gao, Yan, Dial, Laura C., Grazzi, Francesco, & Shinohara, Takenao. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy. United States. doi:10.1080/14686996.2016.1190261.
Tremsin, Anton S., Gao, Yan, Dial, Laura C., Grazzi, Francesco, and Shinohara, Takenao. 2016. "Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy". United States. doi:10.1080/14686996.2016.1190261. https://www.osti.gov/servlets/purl/1313815.
@article{osti_1313815,
title = {Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy},
author = {Tremsin, Anton S. and Gao, Yan and Dial, Laura C. and Grazzi, Francesco and Shinohara, Takenao},
abstractNote = {Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain, texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. Additionally, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.},
doi = {10.1080/14686996.2016.1190261},
journal = {Science and Technology of Advanced Materials},
number = 1,
volume = 17,
place = {United States},
year = 2016,
month = 7
}

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