The major limitation for the continued development of coatings, as well as expanding their range of application, lies in their poor fracture toughness. The coating properties may be enhanced if a distinct second phase material such as ceramic fibers or whiskers are incorporated into the coating structure. This method of coating preparation has the potential of improving the fracture toughness of the coating by a mechanism of bridging the individual lamellae. Ceramic (silico nitride, alumina and zirconia) fibers have been considered in the present study for strengthening thermally sprayed coatings. The technological problems which were encountered during the progress of this study, such as powder manufacture and optimization of the thermal spraying process, are discussed in detail. It is necessary to understand fully the complex structure-property relationships of coatings in order to promote their usage. This work represents a study of the adhesion characteristics of coatings in terms of their microstructure.
Surface and Coatings Technology,
Vol. 37, no. 1 (Feb 1989), pp. 89-110