Accession Number : ADA300258

Title :   Oblique Ultrasonic Backscatter for Detecting Corrosion at Metal-Rubber Interfaces,

Corporate Author : AEROSPACE CORP EL SEGUNDO CA TECHNOLOGY OPERATIONS

Personal Author(s) : Johnson, E. C. ; Lhota, James R. ; Panos, G. C. ; Pollchik, J. D.

PDF Url : ADA300258

Report Date : 15 AUG 1995

Pagination or Media Count : 14

Abstract : An ultrasonic technique for detecting corrosion at metal-rubber interfaces is introduced. The technique, which bears resemblance to the angle beam techniques commonly used in weld inspections, is based on the principle that corrosion pits will backscatter a small percentage of obliquely incident sound. Preliminary data from the study of isolated, artificially induced pits on an aluminum surface are presented. Isolated pits with dimensions on the order of 50 microns are readily detected on the surface of bulk aluminum plates using lO-MHz pulses injected into the plate through a face perpendicular to the surface. Two successful applications of the technique within the aerospace industry are discussed. The first application involves inspection for corrosion in an aluminum-rubber bondline. The second application is to the inspection of a D6AC steel, O-ring sealing surface. (MM)

Descriptors :   *CORROSION, *RUBBER, *ACOUSTIC SCATTERING, *METAL SEALS, METALS, INTERFACES, BACKSCATTERING, STEEL, ALUMINUM, BONDING, AEROSPACE INDUSTRY, HARDNESS, ULTRASONIC TESTS, O RINGS.

Subject Categories : Properties of Metals and Alloys
      Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE