Enhancement of Fatigue Crack Growth and Fracture Resistance in Ti-6Al-4V and Ti-6Al-6V-2Sn Through Microstructural Modification.

Abstract

Significant enhancement of fatigue crack propagation resistance and plan-strain fracture toughness was obtained in commercial-purity Ti-6Al-4V and Ti-6Al-6V-2Sn by microstructural modification. These alloys were studied in 25.4-mm-thick plates with interstitial oxygen contents of 0.20 and 0.17 weight percent, respectively. Heat treatments were chosen to provide widely varied microstructures; they were a mill anneal, a recrystallization anneal, and a beta anneal. The beta anneal was found to be best for improving the crack tolerance properties in question, but it reduced yield strength 9-14% from levels associated with the original mill anneal. The recrystallization anneal significantly enhanced plane-strain fracture toughness and marginally improved fatigue crack propagation resistance with negligible loss of yield strength. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Nov 24, 1976
Accession Number
ADA033687

Entities

People

  • George R. Yoder
  • L. A. Cooley
  • Thomas W. Crooker

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Alloys
  • Chemistry
  • Crack Propagation
  • Cracks
  • Fracture (Mechanics)
  • Heat Treatment
  • Insensitive Explosives
  • Materials
  • Mechanical Properties
  • Mechanics
  • Military Research
  • Resistance
  • Stress Intensity Factors
  • Test Methods
  • Titanium
  • Titanium Alloys
  • Yield Strength

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Polymer Science and Engineering.
  • Structural Health Monitoring of Composite Structures.