A Sensitivity Mapping Technique for Tensile Force and Case Depth Characterization Based on Magnetic Minor Hysteresis Loops

摘要: In the nondestructive testing and evaluation area, magnetic major hysteresis loop measurement technology are widely applied for ferromagnetic material evaluation. However characterization ability of greatly varies as evaluated target properties. To solve this limitation, minor loops, which reflect responses magnetization in a systematic way, is recommend. Inspired by plenty information carried sensitivity mapping technique was developed to achieve highest minor-loop parameters nondestructively targets. study, first time, used measure tensile force steel strand evaluate effective case depth induction-hardened rods. The method procedures given before experimental detection. obtained results indicate that linear correlation between induced voltage (or induction intensity) depth) exists at most locations cluster loops. maps can be optimize field excitation current) analyzed loops achieving sensitivity. For purpose measurement, it suggested should firstly magnetized near-saturation state then restored remanent state. about 15.26 mV/kN. As rods, intensity occurs under low conditions absolute value 0.1110 T/mm. This indicates if required evaluation, rods only weakly magnetized. proposed shows good performance high-sensitivity materials its application scope extended other detection fields.