Electro Ultrasonic Spectroscopy of Magnesium Composites

Electro Ultrasonic Spectroscopy of Magnesium Composites

Peer-reviewed article not indexed in WoS or Scopus

The electro-ultrasonic spectroscopy was used as a non-destructive testing method for the magnesium composites evaluation. AC current varying with frequency fE and the ultrasonic signal varying with frequency fU are applied on the conducting sample and a new intermodulation signal on the frequency fm given by the superposition or subtraction of exciting frequencies is measured on the sample. We have measured on intermodulation frequency fm = fE - fU. This method can be used as a diagnostic tool for the quality and reliability assessment. The sample resistance is influenced by the ultrasonic signal. The ultrasonic signal changes the contact area between the conducting grains in the sample structure and then resistance is modulated by the frequency of ultrasonic excitation. The electrical charge and also the electrical current flowing through the sample structure are conserved. In case the contact area between the conducting grains is changing then the current density is changed. This leads to the resistivity change of measured structure. We suppose that for the sample with more defects in the structure the influence of the ultrasonic signal is more pronounced and the resistance change is higher.

The electro-ultrasonic spectroscopy was used as a non-destructive testing method for the magnesium composites evaluation. AC current varying with frequency fE and the ultrasonic signal varying with frequency fU are applied on the conducting sample and a new intermodulation signal on the frequency fm given by the superposition or subtraction of exciting frequencies is measured on the sample. We have measured on intermodulation frequency fm = fE - fU. This method can be used as a diagnostic tool for the quality and reliability assessment. The sample resistance is influenced by the ultrasonic signal. The ultrasonic signal changes the contact area between the conducting grains in the sample structure and then resistance is modulated by the frequency of ultrasonic excitation. The electrical charge and also the electrical current flowing through the sample structure are conserved. In case the contact area between the conducting grains is changing then the current density is changed. This leads to the resistivity change of measured structure. We suppose that for the sample with more defects in the structure the influence of the ultrasonic signal is more pronounced and the resistance change is higher.

Electric signal, ultrasonic signal, resistance change

Electric signal, ultrasonic signal, resistance change

TOFEL, P.; ŠIKULA, J.; SEDLÁKOVÁ, V.; TRČKA, T.

2011

01.05.2010

0447-6441

Jemná mechanika a optika

55

5/2010

Czech Republic

142

144

3