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Title: Deformation behavior of additively manufactured GP1 stainless steel

Abstract

In-situ neutron diffraction measurements were performed in this paper during heat-treating and uniaxial loading of additively manufactured (AM) GP1 material. Although the measured chemical composition of the GP1 powder falls within the composition specifications of 17-4 PH steel, a fully martensitic alloy in the wrought condition, the crystal structure of the as-built GP1 material is fully austenitic. Chemical analysis of the as-built material shows high oxygen and nitrogen content, which then significantly decreased after heat-treating in a vacuum furnace at 650 °C for one hour. Significant austenite-to-martensite phase transformation is observed during compressive and tensile loading of the as-built and heat-treated material with accompanied strengthening as martensite volume fraction increases. During loading, the initial average phase stress state in the martensite is hydrostatic compression independent of the loading direction. Finally, preferred orientation transformation in austenite and applied load accommodation by variant selection in martensite are observed via measurements of the texture development.

Authors:
 [1];  [1];  [1];  [2];  [2];  [1];  [1];  [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Colorado School of Mines, Golden, CO (United States). Metallurgical and Materials Engineering
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1412890
Alternate Identifier(s):
OSTI ID: 1415899
Report Number(s):
LA-UR-16-28925
Journal ID: ISSN 0921-5093; TRN: US1800396
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing
Additional Journal Information:
Journal Volume: 696; Journal ID: ISSN 0921-5093
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; neutron diffraction; additive manufacturing; stainless steel; in-situ loading; phase transformation

Citation Formats

Clausen, B., Brown, D. W., Carpenter, J. S., Clarke, K. D., Clarke, A. J., Vogel, S. C., Bernardin, J. D., Spernjak, D., and Thompson, J. M. Deformation behavior of additively manufactured GP1 stainless steel. United States: N. p., 2017. Web. doi:10.1016/j.msea.2017.04.081.
Clausen, B., Brown, D. W., Carpenter, J. S., Clarke, K. D., Clarke, A. J., Vogel, S. C., Bernardin, J. D., Spernjak, D., & Thompson, J. M. Deformation behavior of additively manufactured GP1 stainless steel. United States. doi:10.1016/j.msea.2017.04.081.
Clausen, B., Brown, D. W., Carpenter, J. S., Clarke, K. D., Clarke, A. J., Vogel, S. C., Bernardin, J. D., Spernjak, D., and Thompson, J. M. Sat . "Deformation behavior of additively manufactured GP1 stainless steel". United States. doi:10.1016/j.msea.2017.04.081. https://www.osti.gov/servlets/purl/1412890.
@article{osti_1412890,
title = {Deformation behavior of additively manufactured GP1 stainless steel},
author = {Clausen, B. and Brown, D. W. and Carpenter, J. S. and Clarke, K. D. and Clarke, A. J. and Vogel, S. C. and Bernardin, J. D. and Spernjak, D. and Thompson, J. M.},
abstractNote = {In-situ neutron diffraction measurements were performed in this paper during heat-treating and uniaxial loading of additively manufactured (AM) GP1 material. Although the measured chemical composition of the GP1 powder falls within the composition specifications of 17-4 PH steel, a fully martensitic alloy in the wrought condition, the crystal structure of the as-built GP1 material is fully austenitic. Chemical analysis of the as-built material shows high oxygen and nitrogen content, which then significantly decreased after heat-treating in a vacuum furnace at 650 °C for one hour. Significant austenite-to-martensite phase transformation is observed during compressive and tensile loading of the as-built and heat-treated material with accompanied strengthening as martensite volume fraction increases. During loading, the initial average phase stress state in the martensite is hydrostatic compression independent of the loading direction. Finally, preferred orientation transformation in austenite and applied load accommodation by variant selection in martensite are observed via measurements of the texture development.},
doi = {10.1016/j.msea.2017.04.081},
journal = {Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing},
number = ,
volume = 696,
place = {United States},
year = {Sat Apr 22 00:00:00 EDT 2017},
month = {Sat Apr 22 00:00:00 EDT 2017}
}

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Cited by: 4works
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  • Cited by 4
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