Influence of unmelted nanoparticles on properties of YSZ nano-coatings

Abstract

In this work, yttria stabilised zirconia (YSZ) based thermal barrier coatings (TBCs) were deposited by a supersonic atmospheric plasma spray (SAPS). The influence of the unmelted nanoparticles on the thermomechanical properties of the nanostructured YSZ coatings was studied by heat insulation and thermal shock tests. The results indicated that nanostructured SAPS-coatings consisted of nano/micro-grains (60–150 nm) and unmelted nanoparticles (20–50 nm) and exhibited a bimodal microstructure. When the unmelted nanoparticle content increased from 4 to 11%, the Weibull modulus (M) decreased by 46% while the coating’s insulation temperature increased by 32%. The thermal cycling life of the nanostructured SAPS-coating was maximised when the unmelted nanoparticle content reached approximately 8%.

Keywords:

• Thermal barrier coatings
• Supersonic atmospheric plasma spraying
• Nano-particles
• Nanostructured coating

Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant no. 51202187), the National Basic Research Program (grant no. 2013CB035701) and the China Postdoctoral Science Foundation Funded Project (grant no. 2013M530421).