Multi-parameter Evaluation of Magnetic Barkhausen Noise in Carbon Steel

The sensitivity of magnetic Barkhausen noise to many factors has limited its potential application for basic material characterization and detection of residual stress in carbon steel, a common structural material. The present work investigates Barkhausen noise response in plain carbon steel under conditions of varying carbon content, applied elastic stress and different magnetization level. The surface Barkhausen noise measurement system uses a feedback for controlling the flux waveform, which facilitates reproducibility of measurements and also permits extraction of additional parameters from the B-H loop of magnetic circuit. Barkhausen noise parameters correlate with known material parameters, such as coercivity, which vary with carbon content and stress. These results demonstrate the potential for in-situ characterization of carbon steel.