Enhanced high-temperature thermal fatigue property of aluminum alloy piston with Nano PYSZ thermal barrier coatings

Abstract

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.