Eddy current impedance imaging in butt weld joints of AISI stainless steel plates

Eddy current impedance imaging (ECII) is a recently emerging trend in the area of non-destructive testing. Compared to conventional eddy current testing (ECT), ECII gives a global perspective and allows a balanced interpretation. Imaging techniques have the potential of automating the measurement process and providing estimates of defect size from the image data. This paper describes the work carried out at the authors' laboratory with respect to development of the ECII technique as a tool for in-service inspection of welds. Details of the ECII system, implications of probe characteristics and some relevant applications to weld joints are presented.