Environmentally Assisted Cracking of High Strength Beta Titanium Alloys

Abstract

The objective of this research is to define the conditions under which high strength beta-titanium alloys are resistant to environmentally assisted cracking (EAC) in marine environments. Our goals are to: (1) characterize environment enhanced subcritical crack propagation behavior for metallurgical, chemical and mechanical loading conditions that could destabilize crack tip passive films to promote local dissolution and hydrogen uptake, (2) test the hydrogen embrittlement mechanism for EAC, and (3) develop a mechanism- based predictive model of EAC by integrating occluded crack chemistry, surface repassivation, hydrogen uptake and segregation at trap sites, and crack tip process zone micromechanics and damage. The behavior of two peak aged beta alloys, Beta 21S (Ti-15Mo-2.7Nb-3AI by wt% and sigma sub ys = 1380 MPa) and Ti- 15-3 (Ti-15V-3Cr-3AI-3Sn; sigma sub ys = 1315 MPa) plate, was emphasized during this reporting period. Three papers were published; each is summarized as follows. Titanium alloys, Hydrogen embrittlement, Mechanical properties, Intergranular cracking, Transgranular cracking, Microstructure, Alpha precipitates, Beta phase, Hydrides, Passive film, Beta titanium alloys, Fracture threshold.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1992
Accession Number
ADA256196

Entities

People

  • D. G. Kolman
  • G. A. Young Jr.
  • John R. Scully
  • L. M. Young
  • R. P. Gangloff

Organizations

  • University of Virginia

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Biomedical
  • C4I

DTIC Thesaurus Topics

  • Auger Electron Spectroscopy
  • Auger Electrons
  • Chemical Engineering
  • Chemical Synthesis
  • Chemistry
  • Corrosion Resistance
  • Crystal Structure
  • Fracture (Mechanics)
  • Materials
  • Materials Engineering
  • Materials Science
  • Mechanical Properties
  • Mechanics
  • Metallurgy
  • Military Research
  • Spectra
  • Transition Temperature

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Powder metallurgy of Titanium alloys.