Observations of Star Fracture and Longitudinal Splitting in BIS 812 EMA and Q1N Submarine Construction Steels,

Abstract

The tensile properties and fracture behaviour of two submarine construction steels, BIS 812 EMA and Q1N, have been studied. Their properties and fracture behaviour were measured over a wide range of test temperatures utilizing plain and notched tensile specimens. The yield strength of both materials was found to increase with decreasing temperature and the fracture surface appearance of these steels was also temperature dependent. Under certain conditions star fracture was exhibited, rather than the usual cup-and-cone type fracture. The predominance of the star type fracture increased with decreasing temperature in both plain and notched tensile specimens, however, it was suppressed by notching. This paper describes in detail the fractographic features of the surfaces and proposes that a range of conditions exist under which star fracture occurs in these materials. (AN)

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1995
Accession Number
ADA299359

Entities

People

  • D. S. Saunders
  • I. A. Burch

Organizations

  • Defence Science and Technology Group

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Acquisition
  • Alloys
  • Composite Materials
  • Construction
  • Electron Microscopes
  • Electron Microscopy
  • Failure Mode And Effect Analysis
  • Materials
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Microscopy
  • Observation
  • Stress Intensity Factors
  • Tensile Properties
  • Tensile Strength
  • Yield Strength

Fields of Study

  • Materials science

Readers

  • Astronomy/Astrophysics
  • Mathematics or Statistics
  • Structural Health Monitoring of Composite Structures.