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trajectory back to runway, and (vi) idle/taxi after landing. The

results show that the TBC thermal gradient experimental data

in turbine engines can be replicated in the laser gradient rig,

leading to an important tool to better engineer TBCs.

“PLASMA-SPRAYED THERMAL BARRIER

COATINGS WITH ENHANCED SPLAT BONDING

FOR CMAS AND CORROSION PROTECTION”

Tao Liu, Shu-Wei Yao, Li-Shuang Wang, Guan-Jun Yang,

Cheng-Xin Li, and Chang-Jiu Li

The infiltration of molten CMAS in thermal barrier coat-

ings (TBCs) at high temperature is significantly affected by

the microstructure of the ceramic coating. Enhancing the

bonding ratio between splats can reduce the interconnected

pores and suppress infiltration of the molten CMAS into the

coating. In this study, a dual-layered (DL) TBC with the dense

8YSZ on top of the conventional porous 8YSZ was proposed

to enhance CMAS corrosion of atmospheric plasma-sprayed

YSZ. The dense YSZ coating with improved lamellar bonding

was deposited at a higher deposition temperature. The mi-

crostructure of the coatings before and after the CMAS attack

test was characterizedby scanning electronmicroscopy. It was

revealed that by adjusting the microstructure and applying a

dense ceramic layer with the improved interface bonding on

Microstructure of DL-8YSZ coating deposited by APS.

top of porous TBC, infiltration of CMAS into the porous YSZ

coating can be effectively suppressed. Moreover, by designing

DL TBCs, the thermal conductivity of the TBC system exhibits

a limited increase. Thus with the design of the DL structure,

TBCs with high CMAS corrosion resistance and low thermal

conductivity can be achieved.