Complex-Valued Multifrequency Eddy-Current Datasets for Radius Identification of Metallic Spheres

This repository contains the two complex-valued multifrequency eddy-current datasets used in the study entitled “Complex-Valued Transformer for Radius Identification of Metallic Spheres in Eddy Current Testing.” All numerical samples were independently generated in MATLAB using the stabilized analytical formulation described in the associated manuscript. The datasets cover titanium-alloy and bearing-steel spheres with radii of 3, 6, 9, 12, and 15 mm. Six lift-off distances of 1, 2, 4, 6, 8, and 10 mm were considered. For the titanium-alloy dataset, six uniformly spaced relative-permeability values between 1.000 and 1.006 were used, while the electrical conductivity was fixed at 1.6 MS/m. For the bearing-steel dataset, the relative permeability ranged from 100 to 900 in increments of 10, while the electrical conductivity was fixed at 8.0 MS/m. Each sample contains a complex-valued spectrum evaluated at 100 logarithmically spaced excitation frequencies. The frequency range is 1 kHz–1 MHz for titanium alloy and 1 Hz–1 MHz for bearing steel. The titanium-alloy dataset contains 180 samples, whereas the bearing-steel dataset contains 2,430 samples. Sphere radii of 3, 6, 9, 12, and 15 mm correspond to classification labels 0, 1, 2, 3, and 4, respectively. These datasets are provided to support the reproduction and evaluation of metallic-sphere radius classification using multifrequency eddy-current responses.