Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/41731

Title

Influence of plasma spray parameters on the cracking behavior of yttria stabilized zirconia coatings

Author(s)

Kucuk, Ahmet;  Dambra, C. G.;  Berndt, Christopher C.

Abstract

Thermal spray coatings enhance the material properties of substrates but this attribute may be negated if the coatings themselves fail. This paper investigates the performance of an important family of coatings as one step in improving the resistance of the coating/substrate system to mechanical failure. Thermal barrier coatings of yttria partially stabilized zirconia (YSZ) with a NiCrAlY bond coat were air plasma sprayed onto mild-steel substrates. The spray process parameters were varied according to top and bond coat thickness, stand off distance, and substrate temperature. These 17 groups of coating types, with six identical samples in each group, were four point bend tested while coupled with an in-situ acoustic emission transducer. Optical microscopy was then used to examine and map the resulting crack patterns. Measurements of the number of cracks, crack separation, delaminating length, and micro-crack density were also made. The combination of this information, along with properties obtained from the four point bend tests and acoustic emission signals, provided insight into the cracking and delaminating processes.

Publication type

Journal article

Source

Practical Failure Analysis, Vol. 1, no. 1 (Feb 2001), pp. 55-64

Publication year

2001

Keyword(s)

Acoustic emission;  Cracking behavior;  Four-point bending;  Thermal barrier coatings;  YSZ;  Yttria partially stabilized zirconia;  Zirconia

Publisher

Springer

ISSN

1529-8159

Publisher URL

http://dx.doi.org/10.1361/152981501770353247

Copyright

Copyright © ASM International 2001.

Peer reviewed