Magnetic Memory Testing Method on Detecting Stress Distribution of Mechanical Components with Weak Ferromagnetism

摘要

A specific investigation on the corresponding connection between stress condition and external leakage magnetic field of carrying components with weak ferromagnetism subjected to heavy load-bearing situation in geomagnetic field is made in this disquisition. By the detailed analysis of the superficial magnetic signals, obtained by the metal magnetic memory testing technique, in the static tensile tests on bolted connections of two dissimilar materials, S45C and CuAl8Fe5Mn13 (weak ferromagnetic material) specifically, a phenomenon that the abrupt change of signals of CuAl8Fe5Mn13 certainly reveals stress concentration, though the mean amplitude of signals is much smaller comparatively, was found without effort. Subsequently, with supplementary magnetic signal processing and finite element analysis (FEA), a corresponding conclusion is not arduous to draw that evaluation of stress condition and detection of micro cracks on weak ferromagnetism components with metal magnetic memory (MMM) testing method is feasible.