1. Field of the Invention
This invention relates to modified and improved layered lubricants, such as molybdenum disulfide and graphite.
2. Description of Related Art
Layered substances such as molybdenum disulfide, tungsten disulfide and graphite have been used in the past, both as dry lubricants and as additives dispersed in liquid lubricants to reduce the friction and wear between moving surfaces. These materials initially improve the anti-wear properties and lower the friction when used as a solid lubricant. However, as the two surfaces continue to move against each other, the lubricating particles tend to spread away from the asperity contact points. This results in an increase in the friction.
An example is the case of a drill bit rotating against a metal surface while drilling a hole. Within seconds of drilling, the rotating action makes a solid lubricant move away from the tip of the drill and thus increases the friction between the surfaces in contact. It would be desirable to provide some means for maintaining solid lubricants in position between the moving surfaces where they help to reduce the friction instead of being dispersed away from this area.