Thermographic Assessment of the Heat Dissipation Associated with Fatigue Crack Growth in Mild Steel

Abstract

This report examines the feasibility of predicting rates of crack growth in mild steel based on an evaluation of the crack tip dissipated energy A numerical scheme is developed to provide a basis for the computation of dissipated power from measurements of temperature acquired using remote infrared detection. An experimental study is then described where measurements of crack-growth rate in mild-steel coupons exposed to constant amplitude cyclic loading are related to calculations of power dissipation. A simple linear relationship is indicated, with testing also providing some evidence of geometry independence, a key finding with regard to the possible use of dissipated energy as a fatigue characterization parameter. However, further testing involving a more complex loading sequence led to a noticeable change in relationship indicating that the heat dissipation rate is unlikely to offer a simple basis for the prediction of crack growth rate under all loading conditions.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 2001
Accession Number
ADA395590

Entities

People

  • N. Rajic

Organizations

  • Defence Science and Technology Group

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Airframes
  • Australia
  • Boundaries
  • Crack Tips
  • Department Of Defense
  • Detection
  • Detectors
  • Energy Conservation
  • Engineering
  • Engineers
  • Equations
  • Geometry
  • Infrared Detection
  • Materials
  • Mechanical Engineering
  • Mechanics
  • Universities

Readers

  • Materials Science (Mechanical Engineering).
  • Structural Health Monitoring of Composite Structures.
  • Thermal Physics or Thermal Science.