K Results and Comparisons for a Proposed Standard C-Specimen

Abstract

Stress intensity factor data from a boundary value collocation method are used to determine the K calibration for a proposed standard C-shaped specimen for fracture toughness testing. The standard specimen can be readily used with hollow cylinders which have outer-to-inner diameter ratios between 1.2 and 3.0. The K calibration is described in a polynomial form similar to that used with the ASTM standard compact specimen but with an additional term dependent on diameter ratio. Stress intensity factor results from a standard C- specimen with shallow cracks are compared with an analysis based upon the elastic solution for a curved beam under remote bending. K results for mid- depth cracks in the standard C-specimen are compared with compact specimen results and with results from a recently proposed round specimen similar to the compact specimen. Some suggestions are given and anticipated problems are discussed related to testing with the proposed standard specimen.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1974
Accession Number
ADA000681

Entities

People

  • D. P. Kendall
  • J. H. Underwood

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Bending Stress
  • Calibration
  • Classification
  • Diameters
  • Fracture (Mechanics)
  • Geometric Forms
  • Geometry
  • Intensity
  • Materials
  • Materials Testing
  • Measurement
  • Mechanics
  • Nondestructive Testing
  • Standards
  • Stress Intensity Factors
  • Stresses
  • Test Methods

Readers

  • Materials Science (Mechanical Engineering).
  • Mechanical Engineering/Mechanics of Materials.
  • Systems Analysis and Design