Coating Evaluation Using Analytical and Experimental Dispersion Curves
Abstract
Well-bonded or "welded" contact and poorly bonded or "smooth" contact bonds were studied. As examples of welded contact bonds, we used sputtered tantalum and electrodeposited high contraction chromium coatings that were deposited onto steel substrates under controlled conditions. In order to simulate smooth contact coatings, thin sheets of nickel and tantalum were epoxied to copper and steel substrates, respectively. We used the method originated by Cielo et al. to gather data consisting of laser generation of the surface waves in an annular ring and laser detection in the center. Wavelet techniques were used on the surface wave-detected signals in order to obtain the experimental dispersion (velocity-frequency) curves. The experimental dispersion curves were compared to theoretical curves to give insight into the bond quality. It was found that the experimental results correlated well with the theory for the welded case.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1999
- Accession Number
- ADA371275
Entities
People
- Bradford G. Knight
- J. Braunstein
- J. F. Cox
- J. I. Frankel
- M. Hussain
Organizations
- United States Army Armament Research, Development and Engineering Center