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

Title: Creep deformation mechanism mapping in nickel base disk superalloys

Abstract

We investigated the creep deformation mechanisms at intermediate temperature in ME3, a modern Ni-based disk superalloy, using diffraction contrast imaging. Both conventional transmission electron microscopy (TEM) and scanning TEM were utilised. Distinctly different deformation mechanisms become operative during creep at temperatures between 677-815 °C and at stresses ranging from 274 to 724 MPa. Both polycrystalline and single-crystal creep tests were conducted. The single-crystal tests provide new insight into grain orientation effects on creep response and deformation mechanisms. Creep at lower temperatures (≤760 °C) resulted in the thermally activated shearing modes such as microtwinning, stacking fault ribbons and isolated superlattice extrinsic stacking faults. In contrast, these faulting modes occurred much less frequently during creep at 815 °C under lower applied stresses. Instead, the principal deformation mode was dislocation climb bypass. In addition to the difference in creep behaviour and creep deformation mechanisms as a function of stress and temperature, it was also observed that microstructural evolution occurs during creep at 760 °C and above, where the secondary coarsened and the tertiary precipitates dissolved. Based on this work, a creep deformation mechanism map is proposed, emphasising the influence of stress and temperature on the underlying creep mechanisms.

Authors:
 [1];  [2];  [1];  [1]
  1. The Ohio State Univ., Columbus, OH (United States). Center for Electron Microscopy and Analysis
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC); GE University Strategic Alliance
OSTI Identifier:
1328294
Grant/Contract Number:  
AC05-00OR22725; 1534826
Resource Type:
Accepted Manuscript
Journal Name:
Materials at High Temperatures
Additional Journal Information:
Journal Volume: 33; Journal Issue: 4-5; Journal ID: ISSN 0960-3409
Publisher:
Maney Publishing
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Ni-base Superalloys; SEM; TEM; STEM; Mechanism map; Creep deformation,

Citation Formats

Smith, Timothy M., Unocic, Raymond R., Deutchman, Hallee, and Mills, Michael J. Creep deformation mechanism mapping in nickel base disk superalloys. United States: N. p., 2016. Web. doi:10.1080/09603409.2016.1180858.
Smith, Timothy M., Unocic, Raymond R., Deutchman, Hallee, & Mills, Michael J. Creep deformation mechanism mapping in nickel base disk superalloys. United States. doi:10.1080/09603409.2016.1180858.
Smith, Timothy M., Unocic, Raymond R., Deutchman, Hallee, and Mills, Michael J. Tue . "Creep deformation mechanism mapping in nickel base disk superalloys". United States. doi:10.1080/09603409.2016.1180858. https://www.osti.gov/servlets/purl/1328294.
@article{osti_1328294,
title = {Creep deformation mechanism mapping in nickel base disk superalloys},
author = {Smith, Timothy M. and Unocic, Raymond R. and Deutchman, Hallee and Mills, Michael J.},
abstractNote = {We investigated the creep deformation mechanisms at intermediate temperature in ME3, a modern Ni-based disk superalloy, using diffraction contrast imaging. Both conventional transmission electron microscopy (TEM) and scanning TEM were utilised. Distinctly different deformation mechanisms become operative during creep at temperatures between 677-815 °C and at stresses ranging from 274 to 724 MPa. Both polycrystalline and single-crystal creep tests were conducted. The single-crystal tests provide new insight into grain orientation effects on creep response and deformation mechanisms. Creep at lower temperatures (≤760 °C) resulted in the thermally activated shearing modes such as microtwinning, stacking fault ribbons and isolated superlattice extrinsic stacking faults. In contrast, these faulting modes occurred much less frequently during creep at 815 °C under lower applied stresses. Instead, the principal deformation mode was dislocation climb bypass. In addition to the difference in creep behaviour and creep deformation mechanisms as a function of stress and temperature, it was also observed that microstructural evolution occurs during creep at 760 °C and above, where the secondary coarsened and the tertiary precipitates dissolved. Based on this work, a creep deformation mechanism map is proposed, emphasising the influence of stress and temperature on the underlying creep mechanisms.},
doi = {10.1080/09603409.2016.1180858},
journal = {Materials at High Temperatures},
number = 4-5,
volume = 33,
place = {United States},
year = {2016},
month = {5}
}

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

Citation Metrics:
Cited by: 3 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

A History of Superalloy Metallurgy for Superalloy Metallurgists
conference, January 1984


A theory of the anomalous yield behavior in L12 ordered alloys
journal, March 1984


Mechanism of 〈112〉/3 slip initiation and anisotropy of γ′ phase in CMSX-4 during creep at 750°C and 750 MPa
journal, September 2003


High-resolution electron microscopy of dislocation ribbons in a CMSX-4 superalloy single crystal
journal, July 2012


Effects of cooling rate and γ′ morphology on creep and stress-rupture properties of a powder metallurgy superalloy
journal, June 1990

  • Bhowal, P. R.; Wright, E. F.; Raymond, E. L.
  • Metallurgical Transactions A, Vol. 21, Issue 6
  • DOI: 10.1007/BF02672587

Effect of primary and secondary precipitates on creep strength of Ni-base superalloy single crystals
journal, February 2000


On the Role of Tertiary γ' Precipitates in the Creep Behaviour at 700�C of a PM Disk Superalloy
conference, January 2004


Creep of CMSX-4 single crystals of different orientations in tension and compression
journal, April 1996


Creep Anisotropy in the Monocrystalline Nickel-Base Superalloy CMSX-4
conference, January 1996


Tension/compression asymmetry in creep behavior of a Ni-based superalloy
journal, August 1999


Shearing of γ′ precipitates by a〈112〉 dislocation ribbons in Ni-base superalloys: A phase field approach
journal, July 2010


The role of stacking fault shear in the primary creep of [001]-oriented single crystal superalloys at 750°C and 750 MPa
journal, February 2001


Microtwinning during intermediate temperature creep of polycrystalline Ni-based superalloys: mechanisms and modelling
journal, October 2006

  • Viswanathan, G. B.; Karthikeyan, S.; Sarosi, P. M.
  • Philosophical Magazine, Vol. 86, Issue 29-31
  • DOI: 10.1080/14786430600767750

Strengthening Mechanisms in γ′ Precipitating Alloys
journal, January 1970


Slip and climb processes in γ′ precipitation hardened nickel-base alloys
journal, May 1968


Superlattice stacking fault formation and twinning during creep in γ/γ′ single crystal superalloy CMSX-4
journal, January 2003


Twin formation during creep in single crystals of nickel-based superalloys
journal, July 1999


Deformation twinning
journal, January 1995


The high temperature decrease of the critical resolved shear stress in nickel-base superalloys
journal, December 2001


Modeling microtwinning during creep in Ni-based superalloys
journal, March 2006


Microtwinning and other shearing mechanisms at intermediate temperatures in Ni-based superalloys
journal, August 2009


The mechanisms and temperature dependence of superlattice stacking fault formation in the single-crystal superalloy PWA 1480
journal, October 1991

  • Milligan, Walter W.; Antolovich, Stephen D.
  • Metallurgical Transactions A, Vol. 22, Issue 10
  • DOI: 10.1007/BF02664997

High resolution energy dispersive spectroscopy mapping of planar defects in L12-containing Co-base superalloys
journal, May 2015


Mechanisms of creep deformation in polycrystalline Ni-base disk superalloys
journal, June 2008

  • Unocic, R. R.; Viswanathan, G. B.; Sarosi, P. M.
  • Materials Science and Engineering: A, Vol. 483-484
  • DOI: 10.1016/j.msea.2006.08.148

    Works referencing / citing this record:

    The Effect of a Grain Boundary Pinning B2 Phase on Polycrystalline Co-Based Superalloys with Reduced Density
    journal, June 2018

    • Freund, Lisa P.; Stark, Andreas; Kirchmayer, Andreas
    • Metallurgical and Materials Transactions A, Vol. 49, Issue 9
    • DOI: 10.1007/s11661-018-4757-2

    The Effect of a Grain Boundary Pinning B2 Phase on Polycrystalline Co-Based Superalloys with Reduced Density
    journal, June 2018

    • Freund, Lisa P.; Stark, Andreas; Kirchmayer, Andreas
    • Metallurgical and Materials Transactions A, Vol. 49, Issue 9
    • DOI: 10.1007/s11661-018-4757-2