Lift-off invariant inductance of steels in multi-frequency eddy-current testing
نویسندگان
چکیده
Eddy current testing can be used to interrogate steels but it is hampered by the lift-off distance of sensor. Previously, point intersection (LOI) feature has been found for pulsed eddy (PEC) testing. In this paper, a invariant inductance (LII) proposed multi-frequency (MEC) testing, which merely targets ferromagnetic steels. That is, at certain working frequency, measured signal nearly immune Such frequency and are termed as (LIF) LII. Through simulations experimental measurements different under manner, LII verified related sensor parameters independent By referring LIF test piece using an iterative inverse solver, one steel properties (either electrical conductivity or magnetic permeability) reconstructed with high accuracy.
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ژورنال
عنوان ژورنال: NDT & E international
سال: 2021
ISSN: ['0963-8695', '1879-1174']
DOI: https://doi.org/10.1016/j.ndteint.2021.102458