Microstructures and characterization of zirconia-yttria coatings formed in laser and hybrid spray process |
| |
Authors: | Z Zhou H Shirasawa N Eguchi A Ohmori |
| |
Affiliation: | (1) Research and Development Department, The Advanced Materials Processing Institute Kinki Japan, 7-1-8 Doicho, Amagasaki-City, 660-0083 Hyogo, Japan;(2) Aluminum and Copper Division Technical Department, KOBE Steel, Ltd., Fujisawa, 251-8551 Kanagawa, Japan;(3) Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, 567 Ibaraki-city, Osaka, Japan |
| |
Abstract: | Hybrid plasma spraying combined with yttrium-aluminum-garnet laser irradiation was studied to obtain optimum zirconia coatings
for thermal barrier use. Zirconia coatings of approximately 150 μm thickness were formed on NiCrAlY bond coated steel substrates
both by means of conventional plasma spraying and hybrid plasma spraying under a variety of conditions. Post-laser irradiation
was also conducted on the plasma as-sprayed coating. The microstructure of each coating was studied and, for some representative
coatings, thermal barrier properties were evaluated by hot erosion and hot oxidation tests. With hybrid spraying, performed
under optimum conditions, it was found that a microstructure with appropriate partial densification and without connected
porosity was formed and that cracks, which are generally produced in the post-laser irradiation treatment, were completely
inhibited. In addition, hybrid spraying formed a smooth coating surface. These microstructural changes resulted in improved
coating properties with regard to hardness, high temperature erosion resistance, and oxidation resistance.
This paper originally appeared in Thermal Spray: Meeting the Challenges of the 21st Century; Proceedings of the 15th International Thermal Spray Conference, C. Coddet, Ed., ASM International, Materials Park, OH, 1998. This proceedings paper has been extensively reviewed according
to the editorial policy of the Journal of Thermal Spray Technology. |
| |
Keywords: | densification hot erosion resistance hybrid spraying NiCrAlY oxidation resistance plasma-spraying roughness thermal barrier coating yttrium-aluminum-garnet zirconia |
本文献已被 SpringerLink 等数据库收录! |
|