磁致伸缩导波激励传感器模型及输出特性  

Exciting Model and Output Characteristics of Magnetostrictive Sensor for Guided Wave

作　　者：龙盛蓉[1,2] 钟毓宁[3] 宋小春[3] 李志农[2] 刘莹[1] 

机构地区：[1]南昌大学机电工程学院,南昌330068 [2]南昌航空大学无损检测技术教育部重点实验室,南昌330063 [3]湖北工业大学机械学院,武汉430068

出　　处：《振动．测试与诊断》2014年第4期757-761,784-785,共5页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(51261024,50875077);教育部科学技术重点研究资助项目(211110);湖北省优秀中青年科技创新团队计划资助项目(T201105)

摘　　要：基于MsS传感器存在较低的信噪比、在外加磁场作用下非线性力磁耦合特性造成输出特性变化等问题,从铁磁性材料非线性磁弹性耦合理论及磁致伸缩导波激励传感器模型出发,建立了磁致伸缩导波产生的动力学模型。分析了偏置磁场、激励频率及激励电流对介质质点振动幅度的影响,通过有限元仿真计算方法验证了该模型分析的有效性。以该模型为基础讨论了非线性模型与线性模型对介质质点振动位移影响,进一步说明了该模型的适用性。分析表明,在考虑频散特性的情况下,为提高磁力转换效率应选择频率较低而强度较大的激励电流,且其偏置磁场应选择在质点振幅曲线中切线斜率最大的位置。The magnetostrictive sensor(MsS)of guided wave is a new type of ultrasonic testing device used for the structural health monitoring(SHM)of systems.Its use can be limited by its shortcomings:It has low signal to noise ratio,and its output is affected by the nonlinear magneto-mechanical coupling performance under a magnetic field.In order to solve these problems,a dynamics mechanical model is set up for MsS guided wave generation on the nonlinear magneto-mechanical coupling performance of ferromagnetic material.The effects of the bias magnetic field,excitation frequency,and excitation current on the particle amplitude are analyzed.The dynamics mechanical model is verified with the FEM method.The difference in particle amplitude between the nonlinear and linear model is discussed,which further proves the model′s applicability.The results indicate that low frequency,heavy current,and suitable bias magnetic field can improve the conversion efficiency of the magneto-mechanical coupling performance under conditions of considering dispersion.The suitable bias magnetic field is determined by the maximum tangent slope of the amplitude curve.

关 键 词：磁致伸缩 超声传感器 铁磁性材料 导波 动力学模型 

分 类 号：TB512[理学—物理]