A surface acoustic wave technique for monitoring the growth behavior of small surface fatigue cracks
The theory of Kino and Auld which relates the reflection coefficient of acoustic waves from a crack to its size is summarized. A scattering model is evaluated from this theory concerning the reflection of surface acoustic waves (SAW) from a small surface fatigue crack at a frequency such that the crack depth is much smaller than the acoustic wavelength. Acoustic predictions of crack depth are compared to postfracture measurements of depth for small surface cracks in Pyrex glass, 7075-T651 aluminum, and 4340 steel. Additionally, the minimum detectable crack depth as limited by the acoustic noise level is determined for several typical aluminum and steel alloys. The utility of SAW reflection coefficient measurements for inferring crack depth, crack growth, and crack opening behavior in situ during fatigue cycling is discussed.
- Research Organization:
- Stanford Univ., Stanford, CA
- OSTI ID:
- 6776267
- Journal Information:
- J. Nondestr. Eval.; (United States), Journal Name: J. Nondestr. Eval.; (United States) Vol. 5:1; ISSN JNOED
- Country of Publication:
- United States
- Language:
- English
Similar Records
Evaluation of surface fatigue cracks using Rayleigh waves. Ph.D. Thesis
The application of a logic framework for fatigue crack growth analyses to microstructural effects
Related Subjects
360103* -- Metals & Alloys-- Mechanical Properties
ACOUSTIC MONITORING
ACOUSTIC TESTING
ACOUSTICS
ALLOYS
ALUMINIUM ALLOYS
ALUMINIUM BASE ALLOYS
BOROSILICATE GLASS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-MOLYBDENUM STEELS
CRACK PROPAGATION
CRACKS
DEPTH
DIMENSIONS
FATIGUE
GLASS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS TESTING
MECHANICAL PROPERTIES
MONITORING
NONDESTRUCTIVE TESTING
PYREX
REFLECTION
SIZE
STEELS
TESTING
WAVE PROPAGATION