Air-coupled ultrasonic ferroelectret receiver with additional bias voltage
- High sensitivity is an important requirement for air-coupled ultrasonic sensors applied to materials testing. With a lower acoustic impedance than any piezoelectric material, charged cellular polypropylene (PP) offers better matching to air with a similar piezoelectric coefficient. The piezoelectric properties of charged cellular PP originate from their polarization, creating permanent internal voltage. The sensitivity of the sensor can be increased by applying additional dc bias voltage, as it has been done already for transmitters. This work presents the first ultrasonic sensor based on charged cellular PP including a high-voltage module providing dc bias voltage up to 2 kV. This bias voltage led to an increase in the signal-to-noise ratio of up to 15 ± 1 dB. The measurement of the received signal depending on the applied bias voltage is proposed as a new method of determining the internal voltage of ferroelectrets. The sensor combined with a cellular PP transmitter was applied toHigh sensitivity is an important requirement for air-coupled ultrasonic sensors applied to materials testing. With a lower acoustic impedance than any piezoelectric material, charged cellular polypropylene (PP) offers better matching to air with a similar piezoelectric coefficient. The piezoelectric properties of charged cellular PP originate from their polarization, creating permanent internal voltage. The sensitivity of the sensor can be increased by applying additional dc bias voltage, as it has been done already for transmitters. This work presents the first ultrasonic sensor based on charged cellular PP including a high-voltage module providing dc bias voltage up to 2 kV. This bias voltage led to an increase in the signal-to-noise ratio of up to 15 ± 1 dB. The measurement of the received signal depending on the applied bias voltage is proposed as a new method of determining the internal voltage of ferroelectrets. The sensor combined with a cellular PP transmitter was applied to nondestructive testing of a rotor blade segment and glued-laminated timber, enabling imaging of the internal structure of these specimens with a thickness around 4 cm.…
Autor*innen: | Mate Gaal, Rui Caldeira, Jürgen Bartusch, Florian Schadow, Konrad Vössing, M. Kupnik |
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Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control |
Jahr der Erstveröffentlichung: | 2019 |
Organisationseinheit der BAM: | 8 Zerstörungsfreie Prüfung |
8 Zerstörungsfreie Prüfung / 8.2 Zerstörungsfreie Prüfmethoden für das Bauwesen | |
8 Zerstörungsfreie Prüfung / 8.4 Akustische und elektromagnetische Verfahren | |
Verlag: | IEEE |
Jahrgang/Band: | 66 |
Ausgabe/Heft: | 10 |
Erste Seite: | 1600 |
Letzte Seite: | 1605 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Acoustic sensors; Ferroelectret; Nondestructive testing; Ultrasonic imaging; Ultrasonic transducers |
Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
DOI: | 10.1109/TUFFC.2019.2925666 |
ISSN: | 0885-3010 |
ISSN: | 1525-8955 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 27.09.2019 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 27.09.2019 |