skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Impact of microstructural stability on the creep behavior of cast Al–Cu alloys

Abstract

Creep behavior of three cast Al–Cu alloys at 300 °C was studied by measuring their steady state creep rates as a function of stress. Microalloying additions in two alloys stabilized the θ' (Al2Cu) precipitates to 300 °C, which allowed grain boundary-controlled creep deformation to dominate at low stresses in these alloys. In contrast, the instability of the microstructure at 300 °C in a conventional Al–Cu 206 alloy led to the majority of θ' precipitates transform to the θ phase. The 206 alloy displayed diminished resistance to dislocation motion and a dislocation creep mechanism dominated from the lowest stresses. A modified Coble creep model was developed to describe the experimental low-stress creep rates in the alloys with thermally stable precipitate structures. Finally, it is concluded that increasing the thermal stability of precipitates in Al–Cu alloys can provide significant improvement in their creep performance.

Authors:
ORCiD logo [1];  [2];  [3]; ORCiD logo [3]; ORCiD logo [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Colorado School of Mines, Golden, CO (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Indian Inst. of Technology, Kharagpur (India)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
1607324
Alternate Identifier(s):
OSTI ID: 1579764
Grant/Contract Number:  
AC05-00OR22725
Resource Type:
Accepted Manuscript
Journal Name:
Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing
Additional Journal Information:
Journal Volume: 772; Journal Issue: C; Journal ID: ISSN 0921-5093
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; aluminum alloys; creep; aluminum-copper; grain boundary

Citation Formats

Milligan, Brian K., Roy, Shibayan, Hawkins, Charles S., Allard Jr, Lawrence, and Shyam, Amit. Impact of microstructural stability on the creep behavior of cast Al–Cu alloys. United States: N. p., 2019. Web. https://doi.org/10.1016/j.msea.2019.138697.
Milligan, Brian K., Roy, Shibayan, Hawkins, Charles S., Allard Jr, Lawrence, & Shyam, Amit. Impact of microstructural stability on the creep behavior of cast Al–Cu alloys. United States. https://doi.org/10.1016/j.msea.2019.138697
Milligan, Brian K., Roy, Shibayan, Hawkins, Charles S., Allard Jr, Lawrence, and Shyam, Amit. Wed . "Impact of microstructural stability on the creep behavior of cast Al–Cu alloys". United States. https://doi.org/10.1016/j.msea.2019.138697. https://www.osti.gov/servlets/purl/1607324.
@article{osti_1607324,
title = {Impact of microstructural stability on the creep behavior of cast Al–Cu alloys},
author = {Milligan, Brian K. and Roy, Shibayan and Hawkins, Charles S. and Allard Jr, Lawrence and Shyam, Amit},
abstractNote = {Creep behavior of three cast Al–Cu alloys at 300 °C was studied by measuring their steady state creep rates as a function of stress. Microalloying additions in two alloys stabilized the θ' (Al2Cu) precipitates to 300 °C, which allowed grain boundary-controlled creep deformation to dominate at low stresses in these alloys. In contrast, the instability of the microstructure at 300 °C in a conventional Al–Cu 206 alloy led to the majority of θ' precipitates transform to the θ phase. The 206 alloy displayed diminished resistance to dislocation motion and a dislocation creep mechanism dominated from the lowest stresses. A modified Coble creep model was developed to describe the experimental low-stress creep rates in the alloys with thermally stable precipitate structures. Finally, it is concluded that increasing the thermal stability of precipitates in Al–Cu alloys can provide significant improvement in their creep performance.},
doi = {10.1016/j.msea.2019.138697},
journal = {Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing},
number = C,
volume = 772,
place = {United States},
year = {2019},
month = {11}
}

Journal Article:

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

Save / Share: