0

Full Content is available to subscribers

Subscribe/Learn More  >

Thermomechanical Fatigue of a Directionally-Solidified Ni-Base Superalloy in the Presence of Stress Concentrations

[+] Author Affiliations
Robert A. Kupkovits, Richard W. Neu

Georgia Institute of Technology, Atlanta, GA

Paper No. GT2009-59278, pp. 163-173; 11 pages
doi:10.1115/GT2009-59278
From:
  • ASME Turbo Expo 2009: Power for Land, Sea, and Air
  • Volume 6: Structures and Dynamics, Parts A and B
  • Orlando, Florida, USA, June 8–12, 2009
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 978-0-7918-4887-6 | eISBN: 978-0-7918-3849-5
  • Copyright © 2009 by ASME

abstract

Directionally-solidified (DS) Ni-base superalloys are used in high temperature gas turbines because of their excellent properties in the most aggressive mechanical, thermal, and environmental operating conditions. Complex thermomechanical loading of turbine blades is induced by repeated engine start-up, firing, and shut-down transients. These histories make life prediction for such components difficult and subjective. In addition, accurate techniques need to account for the presence of cooling hole stress concentrations, time-dependent dwells, thermal gradients, and anisotropic material properties. In working towards such an analytical life model, this paper describes the cyclic deformation response and damage mechanisms resulting from thermomechanical fatigue (TMF) of directionally-solidified CM247LC DS. Experimental LCF tests consisted of linear in-phase (IP) and out-of-phase (OP) TMF cycles performed on smooth and notched round-bar specimens in both longitudinal and transverse grain orientations. Results take into consideration anisotropy, time-dependent deformation, and notch effects in addition to the waveform and temperature cycle characteristics. The active damage mechanisms are identified as a function of these parameters. Conclusions are drawn in light of fractography, microscopy, and finite element analysis conducted to evaluate geometric and microstructural influences on material behavior.

Copyright © 2009 by ASME
Topics: Fatigue , Superalloys , Stress

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In