Contactless Mode-Selective Resonance Ultrasound Spectroscopy: Electromagnetic Acoustic Resonance

Published

August 1, 1999

Author(s)

H Ogi, H M. Ledbetter, S D. Kim, M Hirao

Abstract

We describe a noncontacting resonant-ultrasound-spectroscopy (RUS) method for measuring elastic constants and internal friction of conducting materials. This method is called electromagnetic acoustic resonance (EMAR). Contactless acoustic coupling is achieved by energy transduction between the electromagnetic field and the ultrasonic vibrations. By changing the field direction, we can selectively excite and detect a particular vibration mode, an advantage in identifying the vibration modes of the observed resonance peaks. The elastic constants and internal friction measured by EMAR were compared with those by the usual RUS method for a rectangular parallelpiped copper monocrystal. Both methods yielded the same elastic constants despite a fewer resonant peaks in the EMAR case. The two methods gave essentially the same shear-mode internal friction, but the RUS method gave higher volume-mode internal friction.

Citation

Journal of the Acoustical Society of America

Volume

106

Issue

No. 2

Pub Type

Journals

Keywords

elastic constants, electromagnetic acoustic resonance, free vibration, internal friction, noncontact measurement, resonance ultrasound spectroscopy

Citation

Ogi, H. , Ledbetter, H. , Kim, S. and Hirao, M. (1999), Contactless Mode-Selective Resonance Ultrasound Spectroscopy: Electromagnetic Acoustic Resonance, Journal of the Acoustical Society of America (Accessed December 14, 2024)