Accession Number:

ADA093812

Title:

Ultrasonic Non-Destructive Testing of Materials.

Descriptive Note:

Interim rept. no. 2, 1 Aug 78-31 Jul 80,

Corporate Author:

CORNELL UNIV ITHACA NY DEPT OF THEORETICAL AND APPLIED MECHANICS

Personal Author(s):

Report Date:

1980-12-01

Pagination or Media Count:

25.0

Abstract:

This report describes broadband measurements of ultrasonic dispersion and attenuation in cross-plied specimens of graphite-epoxy. Quantitative comparisons of dispersion and attenuation data are made by means of least-square fit algorithms implemented into the ultrasonic signal processing system. Reproducible measurements in graphite-epoxy have been obtained. Two new frequency-dependent attenuation measurement techniques are described for measurements in composite materials. One is a continuous-wave resonance technique and the other is based on the Kramers-Kronig relation to find the attenuation from measurement of the dispersion. The new techniques are expected to be especially useful for measurements in highly absorbent composite specimens. A firm basis for the technique has been established and measurements with graphite-epoxy specimens are described. Good agreement can be obtained between the various attenuation measurement techniques. Author

Subject Categories:

  • Laminates and Composite Materials
  • Plastics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE