Thermal oxidation of aviation lubricating oil: Mechanism, influencing factors, evaluation methods, and antioxidants

Aviation lubricating oil, as the “blood of machine operation”, plays an important role in the lubrication, cooling, cleaning, sealing, rust prevention, and other aspects of aero-engines, thereby ensuring the safe and stable long-term endurance of aero-engines under high-speed and high-temperature conditions. The thermal oxidation of aviation lubricating oil leading to decay is the most important factor causing lubricating oil failure, which will seriously affect the performance of aero-engines and endanger flight safety. Here, we comprehensively summarize the oxidation mechanism of aviation lubricating oil, factors affecting thermal oxidation of aviation lubricating oil, evaluation methods for thermal oxidation of aviation lubricating oil, and antioxidants that inhibit thermal oxidation of aviation lubricating oil. We hope that this review can enhance readers' understanding of the thermal oxidation of aviation lubricating oil, stimulate broader interest, and promote more exciting development in this promising field.