A lubricated ball bearing for use in ball bearing sets is disclosed. The lubricated ball bearing features a lubricating coating applied to its outer surface. The lubricating coating preferably comprises silver, and enables the ball bearing to be utilized in bearing assemblies environments where other lubricants may not be acceptably used, such as in the high vacuum environment of an x-ray tube. The lubricating coating is attached to the ball bearing via an intermediate bonding layer that is interposed between the outer surface of the ball bearing core and the lubricating coating. The intermediate bonding layer, preferably comprising nickel, is chemically bonded to both the ball bearing core and the lubricating coating. This produces a lubricating coating having a high-strength adhesion to the ball bearing such that flaking or degrading of the coating will not occur in the high heat, high vacuum environment of the x-ray tube during x-ray production.