INVESTIGATION OF HOLOGRAPHIC TESTING TECHNIQUES
Semiannual rept. no. 2, 1 Jun-30 Nov 1969
MICHIGAN UNIV ANN ARBOR INST OF SCIENCE AND TECHNOLOGY
Pagination or Media Count:
The report includes studies of interferometric detection of stress corrosion cracking, testing of honeycomb sandwich structures, techniques developed for pulsed-laser contouring and interferometry, laser speckle reduction in interferometry, modulated reference-wave holography, and flaw detection. Holographic interferometry has been used to detect initiation of stress corrosion, monitor the progressing of delayed cracking, and detect bond defects in an aircraft trim tab of honeycomb structure. The several theoretical and experimental investigations conducted include the development of multiple- wavelength holographic interferometry, the study of techniques for improving interferometry of three-dimensional transparent objects, the application of modulated reference-wave holography to vibrating diffusely reflecting objects, and the application of hologram interferometry to detection of flaws in cylindrical steel objects.
- Test Facilities, Equipment and Methods