An Investigation of Mechanisms Effecting Environmental Stress Cracking in Titanium Alloy,

Abstract

The acoustic emission technique was applied to monitor visible crack growth and microcrack formations as energy release in real time in titanium alloy using a 12.8 millimeters (0.510 in) WOL compact specimen in a plane strain mode. The specimens were fatigued in the 30 - 60 Hz range at a determined stress intensity factor (K1) with an acoustic emission transducer at a gain of 85 dB and a bandpass frequency of 0.1 - 0.3 MHz. A stable crack advanced and microcracks formed at angles other than parallel to the advancing stable crack is intermittent energy bursts in or along the boundaries of the grains. The energy release, referred to as 'acoustic emission', is a kind of elastic stress impulse. Crack movement in the order of magnitude 10 to the minus 6 in/cyl were detected.

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Document Details

Document Type
Technical Report
Publication Date
Apr 03, 1980
Accession Number
ADA096752

Entities

People

  • Ira J. Graham

Organizations

  • Southern University

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Emissions
  • Acoustic Signals
  • Amplitude
  • Ceramic Materials
  • Cracks
  • Engineering
  • Environmental Stress Cracking
  • Instrumentation
  • Materials
  • Mechanical Engineering
  • Oxide Films
  • Strain Gages
  • Strain Hardening
  • Stress Cracking
  • Stress Intensity Factors
  • Titanium
  • Titanium Alloys

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Materials Science (Mechanical Engineering).
  • Microwave Engineering.