Eddy Current Analysis for Nuclear Power Materials

Abstract

This paper presents experimental results of eddy current analysis of hydrogen in technically pure titanium alloy. Eddy currents when penetrating various depths change their parameters in relation to material properties. Each layer possesses different degree of hydrogenation and differs in number of defects and their location. The measurement of hydrogenated titanium conductivity in various depths with different angular position of eddy current probe were performed and discussed. Components` surface measurements caused by hydrogenation were registered by currents with the frequency of 10 MHz. The results can be used for the development of new materials with required properties.

Measurements of hydrogenated titanium by electric methods

“…The phase composition was analyzed using the databases (PCPDFWIN and PDF-4+) and the full-profile analysis program (POWDERCELL 2.5). The concentration of hydrogen was changed in depth using a spectrum magnetic analyzer (SMA II, Germany) [2,3]. The direct current resistivity of the titanium samples was measured by the four-probe method.…”

“…For this concentration of hydrogen in the titanium alloy, the δ -hydride was found using the alternative lengthy methods for measuring the positron annihilation [16]. The inflection of a curve is caused by two reasons: 1) hydrogen is accumulated mainly in the surface layers; 2) the layer consisting of δ -hydrides of titanium is formed in the surface layers of titanium during hydrogenation, as stated in [2]. Hydrogenation of titanium is accompanied by the change in the readings of the magnetic spectrometer versus the frequency of the eddy current (Fig.…”

“…the decrease in the transport cross section of scattering Q is compensated by the increase in the atomic volume a . The value of the atomic volume was calculated according the data in Table. In addition, the contribution of different scattering components can be changed (formula (2)). This is connected with the change in the amount of titanium hydrides and the nature of dislocations, as well as with the formation of vacancies.…”

“…Hydrogen interacts with the existing structural defects and initiates the formation of new defects and dislocations [1,2]. This leads to the changes in the electrical resistivity.…”