NONDESTRUCTIVE METHODS FOR THE EVALUATION OF CERAMIC COATINGS.
Rept. for 1 Apr 63-31 Mar 64,
IIT RESEARCH INST CHICAGO ILL
Pagination or Media Count:
This report describes the investigation of methods to evaluate the quality of ceramic and intermetallic coatings used to provide increased oxidation resistance for refractory metals. A survey conducted during the course of the program indicated that the parameters of importance were a coating thickness, composition, and uniformity, b the position, lateral extent and depth of cracks, and c the presence of voids, pinholes, and other discontinuities in the coating. The measurement of coating thickness, and of layer thickness in multilayer coatings, is being approached by beta backscatter measurements. Nuclear methods for determining coating uniformity and the presence of cracks or other discontinuities are also being studied. The ultrasonic investigations have been directed exclusively at the application of Rayleigh wave methods to coating evaluation. Author