弱场激励下铁磁性试件疲劳拉伸磁信号研究

研究了铁磁性材料试件，在弱磁激励条件下进行疲劳拉伸，并检测试件表面沿拉伸方向表面磁场信号的变化及其分布特征。选用16MnR进行试验，对预制缺陷的试件进行弹性范围内的疲劳拉伸。利用基于巨磁阻芯片的阵列式传感器探头进行不同拉伸阶段的试件表面磁场扫描测量，并对信号进行滤波处理和对本征信号及其梯度进行成像。对不同拉伸阶段和传感器阵列中不同传感器通道的磁信号进行了分析，探讨了弱磁激励状态下疲劳拉伸试件表面磁信号对无损性评估铁磁性机械试件的有效性。

Research on Magnetic Signals on Surface of Ferromagnetic Specimen after Tension Fatigue under Weak Magnetic Field

The metal magnetic signals of ferromagnetic specimen under the excitation of weak magnetic field were investigated. The 16MnR was adopted to make the specimen with a prefabricated small crack and then the fatigue tensile experiment was did,a probe based on the GMR array was introduced to scan and pick up the weak magnetic memory signals of the specimen surface under different stages of tension fatigue. The acquired data were filtered and mapped as well as its gradient. Magnetic signals at different stages of tensile fatigue and that of different channels were analyzed. Discussion on the nondestructive evaluation of ferromagnetic components using the method of magnetic memory under weak magnetic field was implemented.