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Thermal barrier coatings (TBCs) have been extensively used in industry to provide thermal fatigue protection. For example, in engine design, TBCs are commonly seen on combustion chamber components of aerospace engines. In this study, Nano Y2O3 partially stabilized zirconia (PYSZ) TBC was applied on the piston to provide thermal fatigue protection for the aluminum alloy piston of natural gas engine, and to improve its high temperature performance and thermal load carrying capacity. This method can eliminate the severe restrictions on the development of the natural gas engine and also can be referenced by other internal combustion engine components. Experiments and simulation analyses were conducted to determine the effects of the Nano PYSZ TBCs on temperature and thermal load distributions. Results showed that the substrate temperature of Nano PYSZ TBCs piston was considerably lower (about 16% or 55 °C lower) than that of the conventional (uncoated) piston, which indicates that TBCs can effectively provide thermal fatigue protection for pistons and reduce thermal damage to pistons. Simultaneously, the top surface temperature of the piston increased about 52% or 179 °C after applying the coatings, which increased the combustion chamber temperature, resulting in an improved the engine thermal efficiency.

Nano ceramic coatings have low thermal conductivity which can provide good heat insulation properties, and therefore they have been widely used in industrial design as thermal barrier coatings (TBCs). In the design of internal combustion engines, TBCs have been used on combustion chamber components to improve engine performance. In this paper, improvement in the working performance of natural gas engines is demonstrated when an aluminum alloy piston is sprayed with a Y2O3 partially stabilized zirconia (PYSZ) ceramic coating. Steady-state thermal analyses were used to determine the effects of the ceramic coating on temperature distributions. Output was compared with results from an uncoated conventional piston using the finite element method. Results show that the temperature at the top surface of coated piston is significantly higher (about 44% or 153 °C higher) than that of the uncoated piston. This higher combustion chamber temperature results in better engine thermal efficiency and lower emissions. Simultaneously, the temperature of the coated piston substrate is much lower (about 12% or 43 °C lower) than that of the uncoated piston. The lower metallic substrate temperature provides better thermal fatigue protection for the piston.

Aluminium alloys in internal combustion (IC) engines may suffer from heat damage. Such heat damage can be mitigated using thermal barrier coatings (TBCs). In this study, the TBC Nano yttria partially stabilized zirconia (PYSZ) is applied as an aggregated powder to an aluminum alloy piston using an atmospheric plasma spray (APS) method. The preparation and application of the Nano PYSZ aggregated powder are critical to its effectiveness as a TBC. IC engine bench experiments were undertaken to provide a baseline against which the effectiveness of the TBC could be judged. The microstructure of the Nano PYSZ aggregated powder and thermal barrier coatings were examined using three instruments: scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and X-ray powder diffraction (XRD). Results from this study show that the Nano PYSZ ceramic TBCs, applied to the aluminum alloy piston using a plasma spraying technique, (a) has a high quality Nano-structure, (b) can effectively resist the thermal shock of high temperature gas in the cylinder and (c) maintains both stable macro characteristics and micro structure during the working cycle of the IC engine. The thermal insulation properties of TBCs were also examined. The thermal analyses describe the distribution of temperature across both the piston and the aluminum alloy substrate. Results desmonstrate the effectiveness of the TBCs in reducing the temperature of the aluminium alloy substrate at the top of piston. One benefit is that the piston can operate effectively at higher temperatures. Specifically, as the thickness of ceramic coating increased from 0.1 mm to 1.4 mm, the maximum temperature of the pistons coated with the TBCs increased from 399 °C to 665 °C. The maximum temperature of the aluminum alloy substrates simultaneously decreased from 336 °C to 241 °C. This study clearly demonstrates the excellent thermal insulation properties of the TBCs and shows that the thermal insulation performance can be significantly enhanced by increasing the thickness of the ceramic layer.