Elastic Constants and Internal Friction of Advanced Materials
Resonant ultrasound spectroscopy (RUS) (Demarest, 1971; Ohno, 1976; Maynard, 1996; Migliori and Sarrao, 1997; Leisure and Willis, 1997) is recognized as a useful method to determine elastic constants of solids, including those with a lower crystallographic symmetry. The usual RUS configuration consists of a well-shaped specimen such as sphere, cylinder, or rectangular parallelepiped and two piezoelectric transducers that sandwich the specimen at opposite corners. The specimen dimensions are typically 1 to 10 mm. One transducer feeds a continuous-wave (CW) sinusoidal vibration and the other detects ultrasonic oscillation. Sweeping frequency, the received amplitude shows peaks at the free-vibration resonance frequencies of the specimen. The frequency response of the amplitude, or the resonance spectrum, thus includes many resonance peaks. The resonance frequencies are then used in an inverse calculation to find the set of elastic constants that give the measured resonance frequencies.
KeywordsResonance Frequency Elastic Constant Internal Friction Vibration Group EMAR Method
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