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Practical Failure Analysis

, Volume 3, Issue 6, pp 33–39 | Cite as

Failure of backstay rod connectors on a luxury yacht

  • R. J. H. Wanhill
Peer Reviewed Articles

Abstract

A backstay rod connector on a luxury yacht fractured while the vessel was docked. The fracture of this connector caused the backstay assembly to fall to the deck. A second connector contained a large crack. Both connectors were made from 17-4 PH stainless steel. One half of the fractured connector was recovered. The fracture initiated by pitting and crevice corrosion and was followed by stress-corrosion cracking (SCC) that ultimately led to the fracture. The second connector most probably cracked in the same way. Adverse conditions inherent to service use of the connectors could have facilitated the stress-corrosion process. Nevertheless, use of a stress-corrosion-susceptible material is unacceptable, and any connectors made from 17-4 PH steel aged below 866 K (1100°F) should be replaced. Candidate replacement materials are stainless steels type 316, Nitronic 50, a duplex steel such as SAF 2205, and 17-4 PH in the H1100 and H1150 conditions.

Keywords

stainless steel stress corrosion yacht 

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Copyright information

© ASM International - The Materials Information Society 2003

Authors and Affiliations

  • R. J. H. Wanhill
    • 1
  1. 1.National Aerospace Laboratory NLRAmsterdamThe Netherlands

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