Accession Number : ADA329519

Title :   The Use of Electrochemistry and Ellipsometry for Identifying and Evaluating Corrosion on Aircraft.

Descriptive Note : Final rept. 15 May 95-14 Aug 97,

Corporate Author : DACCO SCI INC COLUMBIA MD

Personal Author(s) : Dacres, Chester M. ; Davis, Guy D. ; Krebs, Lorrie A. ; Shook, Mark B.

PDF Url : ADA329519

Report Date : 14 AUG 1997

Pagination or Media Count : 49

Abstract : The objective of this SBIR Phase II project was to develop a sensor that could be used by the USAF to monitor the degree of corrosion in aircraft. Electrochemical Impedance Spectroscopy (ElS) has been performed on aluminum alloy samples coated under military specifications. Precise impedance signatures were acquired in order to develop a simple, yet powerful, sensor for the early detection and measurement of corrosion processes on aircraft. Two versions of prototype sensors have been developed in the Phase II effort to obtain the EIS signature utilizing a two-electrode approach. One version is a portable hand-held unit while the second version is permanently attached. The two-electrode approach enables reliable in-situ, real-time analyses of aircraft metal/coating systems under actual service conditions. Results of the Phase II laboratory testing show that the sensors are capable of tracking the corrosion process on the aluminum substrates under a variety of environmental conditions and substrate configurations. Field testing of the portable unit has shown that the technique can be conducted in the field with results comparable to the laboratory.

Descriptors :   *CORROSION, *ELECTROCHEMISTRY, *ELLIPSOMETERS, PORTABLE EQUIPMENT, METALS, MEASUREMENT, MILITARY REQUIREMENTS, LABORATORY TESTS, AIRCRAFT, ALUMINUM ALLOYS, REAL TIME, SPECTROSCOPY, SPECIFICATIONS, PROTOTYPES, SUBSTRATES, COATINGS, RELIABILITY, ELECTRODES, CONFIGURATIONS, PRECISION, SAMPLING, ELECTRICAL IMPEDANCE, HAND HELD.

Subject Categories : Physical Chemistry
      Properties of Metals and Alloys
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE