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Title: Strategy for Texture Management in Metals Additive Manufacturing

Abstract

Additive manufacturing (AM) technologies have long been recognized for their ability to fabricate complex geometric components directly from models conceptualized through computers, allowing for complicated designs and assemblies to be fabricated at lower costs, with shorter time to market, and improved function. Lacking behind the design complexity aspect is the ability to fully exploit AM processes for control over texture within AM components. Currently, standard heat-fill strategies utilized in AM processes result in largely columnar grain structures. Here, we propose a point heat source fill for the electron beam melting (EBM) process through which the texture in AM materials can be controlled. Using this point heat source strategy, the ability to form either columnar or equiaxed grain structures upon solidification through changes in the process parameters associated with the point heat source fill is demonstrated for the nickel-base superalloy, Inconel 718. Mechanically, the material is demonstrated to exhibit either anisotropic properties for the columnar-grained material fabricated through using the standard raster scan of the EBM process or isotropic properties for the equiaxed material fabricated using the point heat source fill.

Authors:
 [1];  [1];  [2];  [1];  [2];  [2];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Manufacturing Demonstration Facility and Materials Science and Technology Division
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Manufacturing Demonstration Facility
Publication Date:
Research Org.:
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:
1361326
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
JOM. Journal of the Minerals, Metals & Materials Society
Additional Journal Information:
Journal Volume: 69; Journal Issue: 3; Journal ID: ISSN 1047-4838
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Kirka, Michael M., Lee, Yousub, Greeley, Duncan A., Okello, Alfred, Goin, Michael J., Pearce, Michael T., and Dehoff, Ryan R. Strategy for Texture Management in Metals Additive Manufacturing. United States: N. p., 2017. Web. doi:10.1007/s11837-017-2264-3.
Kirka, Michael M., Lee, Yousub, Greeley, Duncan A., Okello, Alfred, Goin, Michael J., Pearce, Michael T., & Dehoff, Ryan R. Strategy for Texture Management in Metals Additive Manufacturing. United States. doi:10.1007/s11837-017-2264-3.
Kirka, Michael M., Lee, Yousub, Greeley, Duncan A., Okello, Alfred, Goin, Michael J., Pearce, Michael T., and Dehoff, Ryan R. Tue . "Strategy for Texture Management in Metals Additive Manufacturing". United States. doi:10.1007/s11837-017-2264-3. https://www.osti.gov/servlets/purl/1361326.
@article{osti_1361326,
title = {Strategy for Texture Management in Metals Additive Manufacturing},
author = {Kirka, Michael M. and Lee, Yousub and Greeley, Duncan A. and Okello, Alfred and Goin, Michael J. and Pearce, Michael T. and Dehoff, Ryan R.},
abstractNote = {Additive manufacturing (AM) technologies have long been recognized for their ability to fabricate complex geometric components directly from models conceptualized through computers, allowing for complicated designs and assemblies to be fabricated at lower costs, with shorter time to market, and improved function. Lacking behind the design complexity aspect is the ability to fully exploit AM processes for control over texture within AM components. Currently, standard heat-fill strategies utilized in AM processes result in largely columnar grain structures. Here, we propose a point heat source fill for the electron beam melting (EBM) process through which the texture in AM materials can be controlled. Using this point heat source strategy, the ability to form either columnar or equiaxed grain structures upon solidification through changes in the process parameters associated with the point heat source fill is demonstrated for the nickel-base superalloy, Inconel 718. Mechanically, the material is demonstrated to exhibit either anisotropic properties for the columnar-grained material fabricated through using the standard raster scan of the EBM process or isotropic properties for the equiaxed material fabricated using the point heat source fill.},
doi = {10.1007/s11837-017-2264-3},
journal = {JOM. Journal of the Minerals, Metals & Materials Society},
number = 3,
volume = 69,
place = {United States},
year = {Tue Jan 31 00:00:00 EST 2017},
month = {Tue Jan 31 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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  • Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data. Understanding and controlling texture are important because it affects mechanical and chemical properties. Solidification texture depends on the local heat flow directions and competitive grain growth in one of the six <100> preferred growth directions in face centered cubic alloys. Furthermore, the heat flow directions are examined for various laser beam scanning patterns based on numerical modeling of heat transfer and fluid flow in three dimensions. Here we show that numericalmore » modeling can not only provide a deeper understanding of the solidification growth patterns during the additive manufacturing, it also serves as a basis for customizing solidification textures which are important for properties and performance of components.« less
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