Improvement of Environmental Crack Propagation Resistance in Ti-8Al-1Mo-1V Through Microstructural Modification.

Abstract

A study has been conducted to improve crack tolerance properties of Ti-8Al-1Mo-1V through microstructural modification. Alloy microstructure was modified relative to that associated with the currently used duplex anneal through variations in heat treatment. Measurements were made of (i) fatigue crack growth in air, (ii) stress-corrosion cracking in 3.5% aqueous sodium chloride solution, and (iii) corrosion-fatigue in 3.5% aqueous sodium chloride solution. Results indicate that relative to crack tolerance properties of the duplex-annealed microstructure, the beta-annealed Widmanstatten microstructure offers superior resistance on all three bases of comparison; specifically, a 40-fold improvement in fatigue crack growth resistance in ambient air, a doubling of stress-corrosion-cracking threshold, and a resistance to corrosion-fatigue which exceeds the fatigue crack growth resistance of the duplex anneal in ambient air. Micromechanistic interpretations are discussed as appropriate. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Mar 19, 1979
Accession Number
ADA069084

Entities

People

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

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Crack Propagation
  • Fan Blades
  • Geometry
  • Grain Size
  • Heat Treatment
  • Materials
  • Mechanical Properties
  • Mechanics
  • Military Research
  • Propulsion Systems
  • Resistance
  • Salt Water
  • Stress Corrosion
  • Stress Corrosion Cracking
  • Tensile Strength
  • Titanium Alloys
  • Turbines

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.
  • Metallurgy