Materials science engineers have developed a “metallic glass” gear system that operates at very low temperatures, without lubrication, and provides high strength.
“Metallic glass” has the strength of a metal but sigh the amorphous structure of a glass. Further, parts made from the materials can be injected molded, similar to how plastic parts are made.
Applications include many kinds of robotics, and especially space systems that must operate in extreme temperature conditions.
Source: Metallic glass gears make for graceful robots — ScienceDaily