Technique for generation of unipolar ultrasonic pulses

A transmit-receive switch has been developed that permits the generation and detection of broadband unipolar ultrasonic stress pulses in a pulse-echo mode. Results obtained with conventional planar transducers show that the bandwidths obtained are significantly larger than those realized with conventional ultrasonic pulse-echo techniques. The broadband technique is expected to be applicable to flaw sizing problems encountered in nondestructive evaluation (NDE) and to the measurement of gradients in material properties that can be related to changes in the acoustic impedance.<<ETX>>

[1]  John R. Rice,et al.  On the Estimation of a Crack Fracture Parameter by Long-Wavelength Scattering , 1978 .

[2]  Drew V. Nelson,et al.  Long Wavelength Rayleigh Wave Scattering from Microscopic Surface Fatigue Cracks , 1982 .

[3]  Eytan Domany,et al.  Rayleigh scattering of elastic waves from cracks , 1979 .

[4]  R. K. Elsley,et al.  Test Bed for Quantitative NDE — Inversion Results , 1982 .

[5]  E. Domany,et al.  Elastic Wave Scattering by General Shaped Defects: the Distorted Wave Born Approximation , 1980 .

[6]  James Corones,et al.  Direct and inverse scattering in the time domain via invariant imbedding equations , 1983 .

[7]  K. Fertig,et al.  Inverse Scattering at Low and Intermediate Frequencies , 1980 .

[8]  John R. Rice,et al.  Scattering of long-wavelength elastic waves from localized defects in solids , 1979 .

[9]  R. B. Thompson,et al.  A Comparison of the Inverse Born and Imaging Techniques for Reconstructing Flaw Shapes , 1981 .

[10]  B. Khuri-Yakub,et al.  Unipolar Transducers , 1979 .

[11]  B. Auld,et al.  Acoustic fields and waves in solids , 1973 .

[12]  James A. Krumhansl,et al.  Determination of flaw characteristics from ultrasonic scattering data , 1979 .

[13]  Jon Opsal,et al.  Theory of elastic wave scattering: applications of the method of optimal truncation , 1985 .

[14]  J. Gubernatis,et al.  Interpretation of elastic‐wave scattering theory for analysis and design of flaw‐characterization experiments: The long‐wavelength limit , 1979 .