Detail publikace

Electro Ultrasonic Spectroscopy of Magnesium Composites

Originální název

Electro Ultrasonic Spectroscopy of Magnesium Composites

Anglický název

Electro Ultrasonic Spectroscopy of Magnesium Composites

Jazyk

en

Originální abstrakt

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.

Anglický abstrakt

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.

BibTex


@article{BUT48102,
  author="Pavel {Tofel} and Josef {Šikula} and Vlasta {Sedláková} and Tomáš {Trčka}",
  title="Electro Ultrasonic Spectroscopy of Magnesium Composites",
  annote="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.",
  chapter="48102",
  journal="Jemná mechanika a optika",
  number="5/2010",
  volume="55",
  year="2010",
  month="may",
  pages="142--144",
  type="journal article"
}