non-destructive eddy current (ec) technique has long been used to detect discontinuities in materials. recently, its application has been extended to characterize materials microstructure. in order to identify different microstructures, four plain carbon steel bars with different chemical compositions (aisi 1015, 1035, 1045 and 1080) were used in annealed condition. the pearlite percentage, car...

The purpose of this paper is to introduce a new technique for row spacing measurement in a wire array using giant magnetoresistive (GMR) sensor. The self-rectifying property of the GMR-based probes leads to accurately detection of the magnetic field fluctuations caused by surface-breaking cracks in conductive materials, shape-induced magnetic anisotropy, etc. The ability to manufacture probes h...

Detection and characterization of the material loss due to corrosion in aircraft fuselage joints plays an important role in life management of aging aircraft. Pulsed eddy current has been shown to effectively characterize hidden corrosion in lap splices. However, variation of the probe lift-off and interlayer gap can cause false indications or inaccuracy in quantification. This paper presents t...

an analytical model for a coastal boundary current was used to investigate heat and salt budget of exchange flows in the persian gulf as a marginal sea. coastal boundary currents exchange heat and freshwater with the mosphere and the offshore waters. as heat and salinity fluxes caused by air-sea interaction and eddy activities, different temperature and salinity associated with boundary current...

In the first half of the article, inspection organization and programs are briefly dealt with. This is followed by a more detailed review of inspection, detection and monitoring methods, which comprises visual inspection, radiography, ultrasonic testing, eddy current technique, magnetic particle inspection, the use of liquid penetrant, the electric field signature method, acoustic emission, lea...

The development and implementation of a portable eddy currents testing instrument with heterodyning based measurements is presented in this paper. The instrument is composed by a dedicated electronic measurement circuitry embedded inside a rugged tablet computer for control and visualization and that interfaces a small footprint planar eddy currents probe. A DDS waveform generator and a transco...