王壮杰,严刚,郭树祥,等.超声Lamb波监测铝合金结构疲劳裂纹扩展实验研究[J].机械科学与技术,2023,42(8):1366-1372超声Lamb波监测铝合金结构疲劳裂纹扩展实验研究王壮杰,严刚,郭树祥,汤剑飞(南京航空航天大学航空学院机械结构力学及控制国家重点实验室,南京210016)摘要:对应用超声Lamb波在线监测金属结构裂纹在疲劳载荷作用下的扩展进行了实验研究。制备了含中心裂纹的铝合金平板结构试件,并在试件表面布设了压电晶片传感网络。疲劳实验中,在观测裂纹扩展的同时,采用压电晶片分别进行Lamb波信号的激励和接收,监测驱动器与传感器间的疲劳裂纹扩展行为。通过时域信号处理提取了Lamb波信号峰值点的幅值(AMP)与传播时间(ToF)特征,由柯西隶属度函数定义了改进的信号健康度指标及相应的损伤指标,并评估了健康度指标和损伤指标随裂纹扩展的变化趋势。最后,结合损伤概率成像方法,融合Lamb波激励-接收路径的所有损伤指标,近似表征了裂纹长度的变化,验证了该方法的可行性和有效性。关键词:裂纹扩展监测;超声Lamb波;健康度指标;损伤指标;损伤存在概率成像中图分类号:V214.4文献标志码:ADOI:10.13433/j.cnki.1003-8728.20220084文章编号:1003-8728(2023)08-1366-07ExperimentalStudyonMonitoringofFatigueCrackGrowthforAluminumAlloyStructurewithUltrasonicLambWavesWANGZhuangjie,YANGang,GUOShuxiang,TANGJianfei(StateKeyLaboratoryofMechanicsandControlofMechanicalStructures,CollegeofAerospaceEngineering,NanjingUniversityofAeronautics&Astronautics,Nanjing210016,China)Abstract:Thispaperpresentsanexperimentalstudyonon-linemonitoringofcrackgrowthinmetalstructuresunderfatigueloadingbyusingultrasonicLambwaves.Analuminumalloyplatestructurewithacentralcrackismanufacturedandanetworkofpiezoelectricwafersaremountedonthesurfaceoftheplate.Duringtheprocessoffatiguetest,piezoelectricwafersareusedtoexciteandreceiveLambwavesignalstomonitorthefatiguecrackgrowthbehaviorbetweentheactuatorsandthesensors,mean-while,thecracklengthisobservedinreal-time.Withtimedomainsignalprocessing,thefeaturesofamplitude(AMP)andtimeofflight(ToF)featuresatthepeakpointsofLambwavesignalsareextracted.Animproveddegreeofhealthindexandcorrespond-ingdamageindexaredefinedthroughCau...