Advances and Evaluation of Metal Magnetic Memory NDT Technique
金属磁记忆检测技术研究进展及若干讨论

Metal Magnetic Memory (MMM) is a newly developed magnetic non-destructive testing (NDT) method. It is effective in characterizing the early damage of widely-used ferromagnetic materials and structures in engineering. However, at the present time this technique is still limited as a mechanism investigation and applied as a qualitative NDT tool due to its short history, lack of robust theoretical basis and varied disturbance factors in testing. This review outlines the research progress of the MMM technique in the last decade. Some key points were discussed, including criteria of using MMM technique to judge the damage state (plastic deformation or macro-crack), the character parameters to provide a quantitative evaluation on the testing result, some affecting factors of experimental results, and the physical model to describe such non-elastic magnetic-stress coupling effect. Finally, some future development trends about this technique are suggested.