FRACTURE TOUGHNESS OF SHIP STEELS

Evidence is presented that mild steel often fails to meet Charpy criteria laid down by Hodgson and Boyd in 1958 for avoidance of brittle fracture in ships. Use of thin plate does not confer any automatic protection against brittle failure. Dynamic fracture toughness data are presented at loading rates matched to the various wave loading phenomena experienced by ships' hulls. It is shown that mild steel with very poor Charpy performance can still exhibit satisfactory fracture toughness at low and intermediate strain rates. This explains the generally low incidence of brittle fracture in mild steel hulls. Nevertheless, in circumstances involving low temperature (0 deg C), however, high applied and residual stresses, local slamming, and a plate with properties near the bottom of the mild steel scatterband, fracture could initiate from a small defect. Crack arrest is discussed and recommendations are made for minimum Charpy crystallinity levels for fracture avoidance.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/03060209
• Supplemental Notes:
  • Journal article
• Authors:
  • Sumpter, J D
  • Bird, J
  • Clarke, J D
• Publication Date: 1989-7

Media Info

• Features: References;
• Pagination: 18p., incl. discuss.
• Serial:
  • Naval Architect
  • ISSN: 0306-0209

Subject/Index Terms

• TRT Terms: Fracture properties; Hulls; Steel structures
• Subject Areas: Bridges and other structures; Marine Transportation;

Filing Info

• Accession Number: 00659128
• Record Type: Publication
• Source Agency: Maritime Technical Information Facility
• Files: TRIS
• Created Date: Jul 21 1994 12:00AM