Practical Failure Analysis

, Volume 3, Issue 4, pp 75–80 | Cite as

Metallurgical failure analysis of titanium wing attachment bolts

  • M. E. Stevenson
  • J. L. McDougall
  • K. G. Clin
Peer Reviewed Articles


Two titanium alloy wing attachment bolts from a commercial jetliner failed during the course of a routine service operation. Failure of the bolts occurred during the re-torque process as the wing was being reattached. Metallurgical failure analysis indicated that the fracture mechanism was ductile overload and that the mechanical properties of the bolts were consistent with exemplar bolts that had been supplied. After eliminating other sources of excessive load application, the most probable cause of failure was ascribed to variances between the frictional characteristics of the bolt at the time of re-torque and at the time of initial torque application several years earlier.


aerospace fasteners failure analysis fractography titanium 


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Copyright information

© ASM International - The Materials Information Society 2003

Authors and Affiliations

  • M. E. Stevenson
    • 1
  • J. L. McDougall
    • 1
  • K. G. Clin
    • 2
  1. 1.Metals & Materials Engineers, LLCSuwanee
  2. 2.MDE EngineersSeattle

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