Stress measurement using magnetic Barkhausen noise and metal magnetic memory testing

This paper describes a new compound magnetic testing system using magnetic Barkhausen Noise (BN) and Metal Magnetic Memory (MMM) testing technique for stress measurement. BN has become an important nondestructive technique due to its exceptional material and stress characterization capabilities. MMM is recently developed technique with special ability for defect detection, stress detection and stress history record capacity. In the applied tensile experiment, BN and MMM signal were acquired via BN measurement system and EMS-2003 MMM instrument. Relationships between magnetic signals and applied tensile stresses were derived from experiment results. The correlation of the two methods was investigated. Conclusions were derived based on the experiment results. Further research directions were also highlighted.