Measurement Science and Technology · 2002 · 98 citations · 10 references
Natural SciencesElectrical EngineeringPhysicsElectromagnetismMagnetic MaterialsMetallic MaterialsCoatingsElectrical CharacterizationElectrical ConductivityElectromagnetic InductionMagnetic Thin FilmsMetalsConductive CoatingsEddy Current AnalysisEddy Current TestingEddy CurrentsMagnetic Materials CharacterizationMetallic CoatingsMetallic ConductivityMetallic Conductors
The pulsed eddy‑current technique’s interaction with coated magnetic metals is discussed. The authors applied the pulsed eddy‑current technique to nickel, copper, and zinc layers on copper, nickel, and magnetic steel substrates, calculated theoretical current differences using Tai et al.’s method, recorded measurements with a PEC instrument, and determined coating thickness or conductivity by comparing air‑core coil data to closed‑form solutions. The developed PEC method can determine the thickness or conductivity of metallic coatings on a metal substrate when either the coating or substrate is magnetic. Sci.
A new measurement method has been developed using the pulsed eddy-current (PEC) technique to determine the thickness or conductivity of metallic coatings on a metal substrate for the case when either the coating or substrate is magnetic. We demonstrate this technique for nickel layers (25-200 µm) over copper substrates, copper layers (25-200 µm) over nickel substrates and zinc layers (50-400 µm) over magnetic steel substrates. The theoretical current difference was calculated using the method developed by Tai et al (Tai C C, Rose J H and Moulder J C 1996 Rev. Sci. Instrum. 67 3965-72). All current difference measurements were recorded with a PEC instrument. The determination of coating thickness or conductivity of the metals is based on the comparison of the data taken with air-core coils and theoretical calculation using closed-form solutions. The physical phenomena of the PEC's interactions with the coated magnetic metals are also discussed.
10
Analytical Solutions to Eddy-Current Probe-Coil Problems
C.V. Dodd, W. E. Deeds · Journal of Applied Physics · 1968 · 1.2K citations