Near point-source longitudinal and transverse mode ultrasonic arrays for material characterization

Area of Science:

• Materials Science
• Acoustics
• Geophysics

Background:

• Ultrasonic wave propagation analysis is crucial for material characterization.
• Accurate phase velocity measurements are essential for understanding wave behavior in isotropic media.
• Existing methods may have limitations in accuracy or angular range.

Purpose of the Study:

• To develop and evaluate a novel phase velocity measurement technique for ultrasonic waves.
• To assess the accuracy of the method for different wave modes (P, SV, SH) and incidence angles.
• To validate the method using a homogeneous, isotropic sodalime glass sample.

Main Methods:

• Utilized specially constructed 0.75 MHz ultrasonic transducers to stimulate and receive P and S wave modes.
• Employed arrays of transducers on a sodalime glass prism, an ideal homogeneous, isotropic medium.
• Applied the Radon transform to convert offset-time (x-t) data to intercept time-horizontal slowness (tau-p) domain for analysis.

Main Results:

• Phase velocities were accurately determined for P, SV, and SH wave modes up to significant incidence angles (76°, 64°, 77° respectively).
• Measured phase velocities: P-wave (5724 ± 64 m/s), SV-wave (3411 ± 30 m/s), SH-wave (3467 ± 15 m/s).
• Results showed excellent agreement (<1% difference) with direct transmission measurements (P-wave: 5690 ± 60 m/s, S-wave: 3440 ± 26 m/s).

Conclusions:

• The newly developed phase velocity measurement method demonstrates high accuracy and reliability.
• The Radon transform-based approach effectively analyzes ultrasonic wave propagation in isotropic materials.
• This technique offers a precise tool for characterizing material elastic properties through wave velocity analysis.