The long-term lubrication performance of fluorosilicone oil in satellite attitude control mechanisms has been successfully implemented in Chinese aerospace engineering. Its performance advantages are primarily reflected in its stability and reliability under extreme space environments.

Core Lubrication Mechanism
Fluorosilicone oil forms a low-surface-energy, highly chemically inert lubricating film through the trifluoropropyl (-CF₃) side chains in its molecular structure, significantly reducing the friction coefficient of precision bearings such as momentum wheels and reaction wheels in a vacuum environment. Its main chain consists of silicon-oxygen bonds (Si-O), with a bond energy as high as 422.5 kJ/mol, giving the material excellent thermal stability and radiation resistance. It can maintain stable viscosity over a temperature range of -60℃ to 200℃, meeting the stringent requirements of the satellite's on-orbit thermal cycling (-150℃ to +120℃).

Space Environment Adaptability
In vacuum and high-energy radiation environments, fluorosilicone oil exhibits extremely low volatility (volatility <5% after heating at 200℃ for 4 hours) and excellent oxidation resistance, preventing the generation of corrosive decomposition products such as hydrogen fluoride (HF), thus avoiding contamination of precision optical and electronic components. Its chemical inertness ensures good compatibility with commonly used aerospace materials such as metals, plastics, and elastomers, without the risk of swelling or corrosion.

Engineering Application Evidence
Sinopec Great Wall Lubricants has provided specialized fluorosilicone oil-based lubricants for the attitude control system of the Tiangong space station, ensuring the stable operation of critical mechanisms for more than ten years in orbit. Although the Lanzhou Institute of Chemical Physics initially developed 114 silicone oil for the Fengyun-2 satellite, its technological path laid the material foundation for the development of fluorosilicone oil in aerospace lubrication systems, demonstrating that my country has established a complete chain from basic research to engineering applications. Comparison with PFPE Lubricants

Performance Indicator | Fluorosilicone Oil | Perfluoropolyether (PFPE)
Temperature Range | -60℃ ~ 200℃ | -50℃ ~ 250℃
Density | ~1.25–1.35 g/cm³ | 1.8–2.0 g/cm³
Radiation Resistance | Excellent | Superior
Chemical Resistance | Good | Superior (Resistant to strong corrosive media such as uranium hexafluoride)
Surface Tension | 20–25 mN/m (Lower, facilitates spreading) | 15–20 mN/m
Cost and Processing | Lower, easy to process | Higher, complex synthesis
Fluorosilicone oil offers a better overall cost-performance ratio in momentum wheel bearings operating at low to medium speeds and under heavy loads, making it a preferred alternative to PFPE in non-extreme chemical environments.
Technical Specifications Basis
Although China does not have a dedicated national standard specifically for "fluorosilicone oil in attitude control mechanisms," the material's volatility, thermal stability, electrical insulation, and other indicators can be selected by analogy with GB/T 40540-2021, the Chinese national standard for "Thermal Conductive Silicone Grease for Spacecraft." International standard AMS3217/7B for testing fluorosilicone rubber can also be used as a reference for material verification.