应力诱发铁磁材料预制切口产生的二维弱磁场信号特征研究

Character of Stress-induced Two-dimensional Low Intensity Field on Precut Notch Zone of Ferromagnetic Material

为研究应力诱发切口部位产生的二维自发弱磁场信号特征,制作45CrNiMoVA特种钢板状切口试件,在MTS810型液压饲服实验机上施加轴向拉应力,采用EMS2003磁记忆仪和RM-1磁记忆仪采集不同应力水平下切口部位法向分量Hp(y)信号、水平分量Hp(x)信号,分析弹性变形阶段内二维弱磁信号特征及变化规律。结果表明:拉应力诱发切口部位Hp(x)信号呈现正向磁尖峰特征,Hp(y)信号呈现磁异变波峰波谷特征;Hp(x)信号的尖峰值和水平基线幅值、Hp(y)信号的峰峰值和峰间斜率K值与工作应力存在线性相关性。

In order to investigate the signal character of two-dimensional low intensity field,sheet specimens of 45CrNiMoVA steel were made.Axial stresses were applied to the specimens on a MTS 810 hydraulic servo machine,and an EMS-2003 metal magnetic memory apparatus and an RM-1 metal magnetic memory apparatus were used to collect horizontal component Hp（x） signals and normal component Hp（y） signals.The variations of the two-dimensional low intensity field signals in the elastic deformation stage were analyzed.The results showed that Hp（x） signal curves presented a character of magnetic positive peak,while Hp（y） signal curves presented abnormal magnetic wave crest and hollow under the effect of applied tensile stress.There were linear relationships between the peak values,horizontal baseline mean values of Hp（x） signal curves and the applied tensile stress respectively,in the same way there existed linear relationships between the peak-to-peak value,the peak-to-peak slope coefficient of Hp（y） signal curves and the applied tensile stress respectively.