超薄弹性层超声反射纵波频域定征方法  

Characterization of the Ultra- thin Elastic Layer by Ultrasonic Longitudinal Reflection Wave in the Frequency Domain

作　　者：张锐[1] 万明习[1] 陈晓[1] 曹文武[2] 

机构地区：[1]西安交通大学,西安710049 [2]宾州州立大学

出　　处：《仪器仪表学报》2001年第4期376-379,383,共5页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金 ( 6 96 30 2 0 );美国 Office of Naval Research资助项目 ( 0 0 0 14 -93-1-0 340 )

摘　　要：本文在定义超薄单层弹性介质反射传递函数的基础上 ,提出以单层介质反射传递函数幅度谱、相位谱和复谱为基础的频域定征方法和在最小二乘意义上的反向算法对超薄弹性单层介质的声速、厚度、密度等声学参数进行定征。进一步分析了影响估计准确性的各种因素 ,研究了反射传递函数对材料各参数灵敏度函数在误差传递中的意义。实验结果证实 ,对于铝质超薄单层介质 ,该方法能够准确估计厚度小到 2A low- frequency ultrasonic longitudinal reflection wave frequency- domain method suited forcharacter- izing longitudinal wave velocity,thickness,and density of ultra- thin elastic layer is presented. The reflection transfer function of the ultra- thin layer is derived.In the least squareerror sense,an inverse algorithm is used to estimate the parameters mentioned above on the basis of the amplitude,phase and complex spectrum. An analy- sis of main sources of the estimate deviation is presented.The sensitivity of the reflection transferfunction to pa- rameters and its significance in the transfer of errors has been well discussed.It is observed that the agreement between the nominal and estimation values is excellent.

关 键 词：超薄单层介质 超声波 传递函数 定量无损定征 无损检测 

分 类 号：TB553[理学—物理] TP274.53[理学—声学]