Ultra-miniature eddy-current converter for small defects of deep occurrence search in the area of high-yield-stress steels weld joints

Abstract

The presented study describes a diagram of an eddy-current measuring system built on the basis of a subminiature eddy-current converter, intended for the conducting materials’ study. The article describes the results of testing a designed measuring system for defects search in 6XB2S steel samples, connected by a weld joint. The technology for creating such materials permits the significant impact resistance of finished products and provides an optimal combination of hardness and toughness. However, the defects formed in the material near the weld joint become a serious problem in the operation of such materials. In this study, an assessment of the possibility of searching for model defects hidden by a weld in two steel plates was made. The defects had different linear dimensions (0.3 - 0.9 mm) and occurred at different depths (1 - 2 mm). The developed system showed high efficiency of scanning and searching for defects with linear dimensions up to 0.9 mm. The search for smaller defects required a significant modernization of the developed measuring system - the introduction of a second eddy-current converter. The article presents the data confirming the feasibility of this change in the measuring system and the possibility of using a measuring system with two eddy current converters to search for small defects occurring at a considerable depth.