Molybdenum disulphide (MoS2) is a popular solid film lubricant used in many applications where a lubricant needs to operate at a high temperature. In particular, it is an excellent choice for extreme-pressure (EPL) lubrication in aircraft engines and vacuum systems.

The lubricating properties of MoS2 are based on the sulfide anions and the covalent bond between the molybdenum atoms. This combination provides the lubrication characteristics that are sought by users of a variety of dry lubricants such as greases and oils.

MOS2 lubrication is often superior to graphite, especially in the high-temperature range. It is also effective in vacuum and at low temperatures.

Particle size and coating thickness are important determinants of MoS2 lubrication performance. The higher the particle size, the lower the oxidation rate of the MoS2 coating.

Magnetron Sputtered Coating versus Spray or Blush Methods

The most common application of MoS2 coating is by magnetron sputtering, which produces a coating with a uniform crystal structure. This crystal structure provides the maximum adhesion and cycle life. Other processes, such as burnishing, powder baking, or spray methods, result in a random crystal structure that drastically reduces the lifetime of the coating.

Anti-Scuff Treatment

Using bonded MoS2 film lubricants to abrasive surfaces requires careful pre-treatment of the substrate. The lubrication properties of bonded MoS2 film lubricants can be greatly affected by the environmental atmosphere. This affects friction and wear, and can cause the lubricant to degrade much faster than expected.

Despite this, bonded MoS2 film lubricants have been widely used as solid lubricants for various industrial applications. The lubrication properties are a good match for dry air, inert gas and vacuum environments, where they have found a wide range of uses.