Microwave Scanning and ASW Holographic Techniques for N.D.T.

Abstract

The feasibility of using two new techniques for non-destructive testing applications, one based on the use of microwaves, the other on acoustic surface waves was explored. The microwaves scanning microscope technique differs from other microwaves n.d.t. systems in that it aims not only to determine the existence of a defect, but also to locate it. The location is effected with an accuracy which is more than two orders of magnitude better that the wavelength of the microwaves used. The acoustic surface wave technique differs from those previously employed in that the authors have adopted a holographic technique, whereby it is possible to record the acoustic field along a single line, and from this recover the complete field. It is therefore able to detect defects in the surface of a sample by reconstruction based on a single record. The method is based on the use of a phase sensitive laser probe, followed by subsequent computer reconstruction. Using this technique the authors have been able to detect very small defects on a quartz surface. It is possible that the technique can be used effectively for determining surface flaws in highly polished surfaces.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1976
Accession Number
ADA033879

Entities

People

  • Anis Husain
  • Eric A. Ash

Organizations

  • University College London

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms

DTIC Thesaurus Topics

  • Accuracy
  • Acoustic Holography
  • Acoustic Waves
  • Acoustics
  • Amplitude Modulation
  • Automatic Gain Control
  • Computers
  • Detection
  • Dielectric Permittivity
  • Magnetic Fields
  • Magnetic Properties
  • Materials Science
  • Materials Testing
  • Measurement
  • Surface Acoustic Wave Devices
  • Surface Acoustic Waves
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Approximation Theory.
  • Optical Physics and Photonics.
  • Thin Film Deposition Science.

Technology Areas

  • Directed Energy