A comparison on thermomechanical properties of plasma-sprayed conventional and nanostructured YSZ TBC coatings in thermal cycling

Conventional and nanostructured YSZ coatings were deposited on IN-738 Ni super alloy by atmospheric plasma spray technique. The oxidation resistance of the coating was measured at 1100 °C using an atmospheric electrical furnace. According to the experimental results, nanostructured coatings showed a better oxidation resistance than conventional one. The improved oxidation resistance of the nanocoating could be explained by the change of structure to a dense and more packed structure in this coating. The thermomechanical properties of the coating were tested using thermal cycles, thermal expansion and elastic modulus tests during which nanostructured YSZ coating again showed a better performance by structural stability. The results indicate that the thermal stress within the nanostructured YSZ is lower than of the conventional YSZ.

► Thermomechanical properties of nanostructured YSZ applied by APS to conventional YSZ.
► Nanostructured coatings showed a better oxidation resistance than conventional one.
► The thermal cyclic tests during which nanostructured YSZ coating showed a better performance.
► The thermal stress within the nanostructured YSZ is lower than of the conventional YSZ.