The short answer
Silver is used in some solid-lubricant coatings, including NASA composite bearing coatings. Performance depends on the full material system and tested conditions, not the presence of silver alone.
A solid material can lubricate
Lubrication does not always come from a liquid. Silver is used in some solid-lubricant coatings, where its behavior is part of a carefully designed contact system. In a 2021 study, researchers tested silver-coated bearing materials against steel under conditions representative of aircraft-engine loads, including deficient lubrication. The tested silver showed good damage tolerance relative to the reference materials.
A coating needs its context
NASA provides a different example in its work on oil-free foil bearings. A composite coating called PS304 contains silver and other lubricating additives to reduce friction and wear when the shaft and foil touch during starting and stopping. NASA’s account of the related PS300 family assigns silver a lower-temperature startup role, alongside a lubricant serving higher temperatures.
These examples explain why engineers investigate silver for friction control. They do not establish that any silver-coated jet-engine bearing can survive an oil failure long enough for a safe shutdown. A material test, a bearing system and an aircraft-engine certification are different levels of evidence.
About this edition
Original source and editorial notes
Adapted from original material by Rich Silver. Original source card: Silver fact: supplied original card (publication date not established).
Reviewed 2026-11-05. This edition distinguishes laboratory material tests, NASA composite foil-bearing research and aircraft-engine certification. Silver is one component of a material system, not an oil-failure safety guarantee.