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Metallurgical Transactions A

, Volume 22, Issue 2, pp 377–391 | Cite as

The initiation and growth of fatigue cracks in a titanium aluminide alloy

  • D. L. Davidson
  • J. B. Campbell
  • R. A. Page
Mechanical Behaviour

Abstract

The micromechanics of small, naturally initiated fatigue cracks and large through-thickness fatigue cracks have been studied in the titanium aluminide alloy Super Alpha 2. The microstructure investigated had equal volume fractions ofα 2 and Β phases. Crack growth rates were higher than through α-Β titanium alloys. Initiation of small cracks was found always to occur in theα 2 phase, and small cracks grew belowΔK th, the minimum cyclic stress intensity required for growth of large fatigue cracks. A method previously proposed for reconciling the growth rates of large and small cracks is applied to these results.

Keywords

Metallurgical Transaction Fatigue Crack Crack Growth Rate Fatigue Crack Growth Small Crack 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© The Minerals, Metals and Materials Society, and ASM International 1991

Authors and Affiliations

  • D. L. Davidson
    • 1
  • J. B. Campbell
    • 1
  • R. A. Page
    • 1
  1. 1.Southwest Research InstituteSan Antonio

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