0
RESEARCH PAPERS

Crack Initiation In Grain Boundaries Under Conditions of Steady-State and Cyclic Creep

[+] Author and Article Information
R. Raj

Department of Mechanical Engineering, University of Colorado, Boulder, Colo.

J. Eng. Mater. Technol 98(2), 132-139 (Apr 01, 1976) (8 pages) doi:10.1115/1.3443355 History: Received December 17, 1974; Revised March 12, 1975; Online August 17, 2010

Abstract

Nucleation of intergranular cracks during steady-state and cyclic creep is analyzed in detail. The basis of the analysis is that grain boundary sliding produces stress concentrations at inclusions, ledges and triple-line junctions which leads to nucleation of cracks. The analysis is built upon different facets of the mechanical behavior of grain boundaries such as: sliding with elastic accommodation, diffusional and power law creep accommodation, and the contribution of sliding to the strain rate under power law creep conditions. Inclusions play an important role in fracture since the energy of the inclusion-matrix interface is usually high and since sliding produces stress concentration at inclusions. Triple line fracture is shown to be important during transient creep conditions. Crack initiation is calculated as a function of the following engineering parameters: temperature, strain rate, grain size, inclusions, cyclic frequency and hold time. The results are in broad agreement with experimental observations.

Copyright © 1976 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

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 Journal Articles
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