Details

Autor(en) / Beteiligte

• Adamowski, J.C.
• Buiochi, F.
• Higuti, R.T.

Titel

Ultrasonic material characterization using large-aperture PVDF receivers

Ist Teil von

• Ultrasonics, 2010-02, Vol.50 (2), p.110-115

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2010

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• This work describes the use of a large-aperture PVDF receiver in the measurement of liquid density and composite material elastic constants. The density measurement of several liquids is obtained with accuracy of 0.2% using a conventional NDE emitter transducer and a 70-mm-diameter, 52 - μ m P(VDF–TrFE) membrane with gold electrodes. The determination of the elastic constants is based on the phase velocity measurement. Diffraction can lead to errors around 1% in velocity measurement when using alternatively the conventional pair of ultrasonic transducers (1-MHz frequency and 19-mm-diameter) operating in through-transmission mode, separated by a distance of 100 mm. This effect is negligible when using a pair of 10-MHz, 19-mm-diameter transducers. Nevertheless, the dispersion at 10 MHz can result in errors of about 0.5%, when measuring the velocity in composite materials. The use of an 80-mm diameter, 52 - μ m -thick PVDF membrane receiver practically eliminates the diffraction effects in phase velocity measurement. The elastic constants of a carbon fiber reinforced polymer were determined and compared with the values obtained by a tensile test.