Design of the Eddy Current Sensor of Steel Ball Nondestructive Detection

The ball surface and sub-surface defects can be test by the eddy current nondestructive method. The core part of the eddy current system is the sensor’s design, including the coil and the process of induction signals. At the end, through experiment of detecting a set of defect ball, with a better result. It’s shows that the amplitude of the detection signal is proportional to the depth of the steel balls crack.