Space Tribology of China

Abstract

In recent years, China’s exploration on outer space has been advanced, putting forwards a lot of new challenges to Chinese tribology society. Stable and Efficient lubrication is one of the key issues to guarantee the operation of components under motion in spacecrafts. The complexity of lubrication arises from the harsh environment conditions in space, including the ultra-high vacuum, UV and atomic oxygen irradiation, large temperature gap etc. State Key Laboratory of Solid Lubrication (LSL) has been actively involved in the China’s aerospace exploration for decades and provided a variety of lubrication solutions to rockets, satellites and spacecrafts. A brief review was given on the state-of-art space tribology research in LSL. In the aspect of fluid lubrication, a number of liquid lubricants was developed or under developed, including the synthetic silicon oil, polyalphaolefin (PAO), multiple substituted cyclopentanes (MACs), ionic liquids etc. The physical properties, including the thermal stability, low temperature fluidity and extremely low saturated vapour pressure, were optimized to meet the requirement for space applications. For the solid lubrication, a number of self-lubricating composites or alloys, multilayer films with special nanostructures and compositions, diamond-like carbon film etc were prepared and the properties were investigated. These lubrication techniques can render ultra-low friction and low friction noise, prevention of cold welding in intermittent operating conditions, and extend lubricant endurance life. Simulated labs and facilities were built up in LSL, allowing for on-ground evaluation of their performance inclusive of the service life and the failure mechanism.