Case Studies of Fatigue Crack Growth Using an Improved Micro-Ligament Instability Model.

Abstract

The tensile ligament instability model TLIM has been refined and modified. A large set of new data cases is analyzed using the improved algorithm, most of these with high fidelity. In microstructurally varied titanium alloys, the process zone size is associated with the effective grain size; in structural and alloy steels it decreases with increasing yield strength, presumably here too related to grain refinement. The other fitting parameters, of environmental surface attack, show an internal consistency among the various specimen materials and environments. The modified model is thought to provide an advantageous means of comparing crack propagation data, and, in selected classes of materials, a suitable basis for predicting fatigue propagation life.

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Document Details

Document Type
Technical Report
Publication Date
Jan 30, 1980
Accession Number
ADA083394

Entities

People

  • J. M. Krafft

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Air Platforms
  • Cyber
  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Alloys
  • Aluminum Alloys
  • Crack Propagation
  • Cracks
  • Fracture (Mechanics)
  • Grain Size
  • Heat Treatment
  • Low Temperature
  • Materials
  • Mechanical Properties
  • Mechanics
  • Modulus Of Elasticity
  • Stress Strain Relations
  • Stresses
  • Titanium
  • Titanium Alloys
  • Yield Strength

Fields of Study

  • Materials science

Readers

  • Computational Modeling and Simulation
  • Materials Science (Mechanical Engineering).
  • Systems Analysis and Design