Efficiency investigation of different ferrite shapes by inductive sensing for barkhausen noise non-destructive testing

Magnetic Barkhausen noise testing is a non-destructive technique widely used for the quality control of ferromagnetic materials. From an industrial point of view, the usage of this technique on different specimens and applications requires geometrically suitable sensing elements. Since induction coils are commonly used as sensing components in this method, this study is focused on the efficiency of ferrite shapes by inductive sensors used by Barkhausen noise non-destructive testing. The study aims to evaluate the effective sensing zone and sensitivity of these different shapes of ferrite. The Barkhausen noise signal is the total of induced voltage spikes resulting from magnetic flux impulses with random properties of direction, amplitude, and duration of 2 to 100 μs. These impulses are simplified with a Gaussian function in three main directions, peak height of 10μT and duration of 10 μs. The location of radiation is another investigation parameter to estimate the effective sensing zone of sensors. The amplitude of induced voltage as a measure of the sensitivity and efficiency of each sensor has been analysed by applying the defined signal to different types of sensors. At the end, an innovative sensor configuration with considerable results is proposed.