Propagation of elastic waves through inhomogeneous, anisotropic materials

Technical Report · Wed Nov 25 04:00:00 EST 1992

OSTI ID:6768074

Minachi, A

Ultrasonic nondestructive inspection demands more precise knowledge of sound propagation in materials. An approximate Gauss-Hermite (GM) model was developed a few years ago for the ultrasonic fields radiated into isotropic and anisotropic materials. In this dissertation, the validity of the GM model in a multilayered medium is evaluated. First, a method of finding the elastic constants of anisotropics is given. Comparisons between GM predictions and finite element predictions show good agreement around the central ray direction, but due to Fresnel approximation, the accuracy of GM model degrades away from the forward propagation direction. The GM model was used for sizing delaminations in a multilayered composite structure. This method, utilizing the reflected signal from the delamination, showed considerable improvement over the traditional sizing method. The model, with local ray tracing, was also used to predict the ultrasonic field beyond an irregularly shaped interface (step discontinuity), with good agreement with experiment.

• Research Organization: Ames Lab., IA (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6768074
• Report Number(s): IS-T-1581; ON: DE93006247
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420500* -- Engineering-- Materials Testing
ACOUSTIC TESTING
ALLOYS
ANISOTROPY
CALCULATION METHODS
COMPOSITE MATERIALS
ELASTICITY
FINITE ELEMENT METHOD
HIGH ALLOY STEELS
INSPECTION
INTERFACES
IRON ALLOYS
IRON BASE ALLOYS
JOINTS
LAYERS
MATERIALS
MATERIALS TESTING
MECHANICAL PROPERTIES
NONDESTRUCTIVE TESTING
NUMERICAL SOLUTION
SOUND WAVES
STAINLESS STEELS
STEELS
TENSILE PROPERTIES
TESTING
ULTRASONIC TESTING
ULTRASONIC WAVES
WAVE PROPAGATION
WELDED JOINTS