A Study on the Relationship between Anodic Oxidation and the Thermal Load on the Aluminum Alloy Piston of a Gasoline Engine

In order to analyze the influence of the anodizing process on the thermal load of an aluminum alloy piston, dedicated temperature tests have been carried out using the Hardness Plug method and the results for the anodized piston have been compared with those obtained separately for an original aluminum piston. In addition, numerical simulations have been conducted to analyze the temperature field and thermal stress distribution. Simulations and experiments show that the maximum temperature of the anodized piston is 16.36% and 5.4% smaller than that of the original piston under the condition of maximum torque and maximum power, respectively. The thermal stress of the temperature field of both pistons is within 50 Mpa, which meets the strength requirements of the material at high temperature. However, the area with significant thermal stress of the anodized piston is significantly smaller than that of the original piston. Combined with the fatigue analysis data, it can be seen that the safety factor of the anodized piston greater than 1.8 is 99.13%. Therefore, adopting the anodizing process not only reduces the piston thermal load, but also helps to extend its life and improve its reliability.