Microstructure and Defects Evaluation of Varistors by Ultrasonic Waves in Low Frequency Range

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26220%2F14%3APU111425" target="_blank" >RIV/00216305:26220/14:PU111425 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.4028/www.scientific.net/KEM.592-593.688" target="_blank" >http://dx.doi.org/10.4028/www.scientific.net/KEM.592-593.688</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.4028/www.scientific.net/KEM.592-593.688" target="_blank" >10.4028/www.scientific.net/KEM.592-593.688</a>

Result language

angličtina

Original language name

Microstructure and Defects Evaluation of Varistors by Ultrasonic Waves in Low Frequency Range

Original language description

Each material contains defects and in-homogeneities in a structure volume. It has influence on the properties of material (conductivity, mass density, mechanical properties). Interaction of the ultrasonic waves with defects or in-homogeneities in the solid state is not clear. Electro-ultrasonic spectroscopy can help to clarify this phenomenon. The electro-ultrasonic spectroscopy describes defects and un-homogeneities inside the sample structure. This method is quite different from electro-acoustic effect. Ultrasonic signal is in range from 20 kHz to 150 kHz. Ultrasonic signal changes geometry of the sample in elastic range only. The sizes of cracks are changing also in the sample volume. Conductivity near the area of cracks is strongly changing due to ultrasonic vibrations. It has influence on resistance of the sample which is changing along with a frequency of ultrasonic vibrations. The amplitude of the resistance change depends on the material, number of cracks, size of cracks and Eigen frequencies of the sample excited by ultrasonic wave. We applied the electro-ultrasonic spectroscopy on two types of varistors. It can be useful for understanding the relation between microstructure and mechanical properties of these types of varistors.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2014

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Key Engineering Materials (print)

ISSN

1013-9826

e-ISSN

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Volume of the periodical

465

Issue of the periodical within the volume

1

Country of publishing house

CH - SWITZERLAND

Number of pages

4

Pages from-to

688-691

UT code for WoS article

000336694400157

EID of the result in the Scopus database

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