Electromechanical characterization of ultrasonic NDE systems

Abstract

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Modeling and Measuring All the Elements of an Ultrasonic Nondestructive Evaluation System II: Model-Based Measurements

“…The damping setting, which should not affect the receiver characteristics in this pitch-catch setup, was set at 0. In general, these results and the results similarly obtained with 5-and 10-MHz transducers (see [3]) showed that:…”

“…Figures 7 and 8 show the measured Thevenin equivalent sources and impedances for energy settings 2 and 4 (and damping settings of 0, 5, and 10). Dang, in his thesis [3], also gave the corresponding results for energy settings 1 and 3, which behave similarly to those shown. The left column in each figure shows the magnitude of source strength and right column shows the corresponding magnitude of the internal electrical impedances measured by using the three external impedances.…”

“…2a). In [3] these pulser parameters were obtained experimentally for a Panametrics 5052PR pulser/receiver, which contains a broad-band "spike" pulser. A typical measured output voltage pulse of this pulser/receiver is shown in Fig.…”

“…Thus, to examine the receiver parameters over a broad frequency spectrum, it is necessary to use multiple transducers with different frequencies. In [3], receiver characteristics were obtained for the 5052PR pulser/receiver using 2.25-, 5-, and 10-MHz transducers. Here, however, we will discuss only the results using the 2.25-MHz transducer, since the other cases demonstrated similar behavior.…”

“…By combining the pulser/receiver measurements described above with the cabling and transducer measurements detailed in [2] and [3] and an explicit model for the acoustic transfer function, t A (ω), we can completely characterize the entire ultrasonic measurement process. The specific ultrasonic immersion measurement system we will charac- terize is the two-transducer calibration setup shown in Fig.…”