The oil and heat resistance performance of fluorosilicone oil in turbocharging systems is as follows:

Heat Resistance Limit and Thermal Stability: Fluorosilicone oil can operate stably in a wide temperature range of -60℃ to 250℃ in turbocharging systems. Modified products such as perfluorosilicone oil maintain low volatility and high viscosity retention at 250℃, with a flash point ≥251℃. The Si–O and C–F bonds in its molecular structure provide excellent thermal oxidative stability, effectively resisting chain scission and free radical oxidation at high temperatures. However, existing literature does not provide experimental data on oxidative decomposition during long-term (>1000 hours) operation above 250℃; therefore, it is not recommended for extreme operating conditions continuously above 250℃ (such as the turbine blade root or the direct contact area of the exhaust side bearing).

Oil and Contamination Resistance: Fluorosilicone oil has extremely strong resistance to swelling and degradation from non-polar contaminants such as engine oil, fuel, and EGR condensates (containing water, hydrocarbons, and nitrogen oxides). Experiments show that fluorosilicone rubber (a system homologous to fluorosilicone oil) immersed in gasoline containing 15% methanol for 500 hours showed changes in hardness, tensile strength, and volume of less than 5%, far superior to traditional fluororubber and PAO base oils. Its low surface tension (20–25 mN/m) effectively repels oil sludge and carbon deposits, reducing the risk of lubrication channel blockage.

Material Compatibility and Sealing Synergy: Fluorosilicone oil is highly compatible with mainstream sealing materials in turbocharging systems, such as fluororubber (FKM), graphite sealing rings, and PTFE composite materials, without swelling, hardening, or corrosion. Due to their similar chemical structures (both containing fluorocarbon chains), fluorosilicone oil and fluororubber can form a stable interface at 200–250℃, avoiding the sealing failure caused by swelling in traditional mineral oils. Its lubricating film exhibits excellent adhesion at the metal-rubber contact surface, reducing the friction coefficient by more than 30% and extending the lifespan of bearings and shaft seals.

Engineering Applications and Comparative Advantages: Although there are no direct mass-produced turbocharger applications, fluorosilicone oil has been successfully used in high-speed (>1.4 × 10⁶ rpm), high-temperature (above 121°C) precision equipment such as laser printers and record players, verifying its reliability under extreme shear and thermal loads. Compared to mainstream PAO synthetic oils, fluorosilicone oil has significant advantages in chemical resistance, carbon deposit resistance, and material compatibility. However, PAO is superior in high viscosity index, low-temperature fluidity, and cost-effectiveness. The two have complementary application scenarios: PAO is suitable for conventional high-temperature bearing lubrication, while fluorosilicone oil is suitable for sealing auxiliary lubrication in high-pollution and highly corrosive environments.

Current Technical Limitations: There is a lack of long-term thermal oxidation stability data for fluorosilicone oil above 250°C, and a lack of direct comparative experimental reports with PAO/ester oils in turbocharger systems.  Furthermore, the industry has not yet established standardized application specifications. Its high cost and low polarity result in insufficient wettability with water-based coolants or oxygen-containing fuels, limiting its comprehensive replacement as a primary lubricant.