Experimental issues in the measurement of nonlinearity parameter from static displacement (dc component) generation experiments
23 Mar 2009-Vol. 1096, Iss: 1, pp 224-230
TL;DR: In this paper, the abnormal behavior of the nonlinearity parameter evaluated from static displacement generation-based finite amplitude ultrasonic wave propagation experiments at low input amplitudes is considered and the cause of the abnormal variation is found to be due to the resolution of the digitizer.
Abstract: Abnormal behavior of the nonlinearity parameter evaluated from static displacement generation based finite amplitude ultrasonic wave propagation experiments at low input amplitudes is considered. Systematic experiments have been conducted on various materials by selectively replacing the instrumentation used on the transmitter and receiver side to explore the plausible contributions from each of the equipment used. The cause of the abnormal variation is found to be due to the resolution of the digitizer. Our study suggests that high resolution digitizers should be used for making reliable measurements at low input amplitudes.
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TL;DR: In this article, the use of non-linear ultrasonic techniques for the characterization of material degradation in 99.98% pure copper due to high-temperature creep was described, where flat dog-bone-shaped specimens were subjected to constant load creep testing at different stress and temperature levels.
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26 citations