What is Molybdenum Disulfide and why is it showing a good lubricating behavior?

Molybdenum Disulfide, also known as Molybdenum Disulphide, MoS2 and Moly, is one of the most widely used solid film lubricants. Like graphite and tungsten disulfide (WS2), MoS2 is a dichalcogenide. The lubricating properties of molybdenum disulfide lubricant are due to a weak atomic interaction (Van der Waals Force) of the sulfide anions, while the covalent bond within the molybdenum is strong.

Which are the easiest and widely recognized ways of applying MoS2 coating?

There are a number of ways to apply MoS2 low friction coatings to the desired substrate. These include:

  • Rubbing and burnishing
  • Impingement with or without inorganic binder
  • Spraying or dipping paint like substance containing the molybdenum disulfide as a lubricant
  • Physical vapor deposition

Some of the specifications covering this application are; MIL-PRF-46010, AS5272, AMS2526.

Why molybdenum disulfide coating is considered unbeatable in comparison to its competitors?

In moving/mating components, the friction causes considerable loss of energy, poorer performance, and limits the wear life of the components. Molybdenum Disulfide can provide a low coefficient of friction, sometimes as low as 0.05 COF. This will be dependent on the humidity, cleanliness, and sliding conditions of your application.

Also, the molybdenum disulfide dry lubricant can:

  • Operate in a wide range of temperatures up to 600 deg F and maintain its lubricity in high load, high-speed conditions.
  • Be very effective in inhibiting corrosion as well when combined with the proper resins and binders.

Lubrication relies on the slippage along with the sulfur atoms. All of the properties of the lamella structure are intrinsic and no external form of moisture is required (as it is with graphite). Mos2 performs best when water vapor is not present, making molybdenum disulfide coating ideal for vacuum applications.

Coating Specifications

Silver Grey
Coefficient of Friction0.06 to 0.15
SubstratesAll ferrous or non-ferrous metal
Man-made solids & plastics
Cure TimeNo cure time is required when applied at ambient temperature
ApplicationsChucks, Collets and Tools
Circuit Breakers and Switches
Compressors and Rheostats
Cryogenic Pumps
Electrical Connectors
Engine and Drive Train Parts
High Vacuum Applications
Machine tools, Pins, Taps
Magnetic Heads
Pilot Valves, Chain Saws
Rubber Gaskets, “O” Ring Seals
Seamer Rolls
Slide Mechanisms

Environmental Specifications

Relative Load Carrying250,000 PSI
Ambient Temperature Range-185 to 350 ºC
Vacuum Temperature Range-185 to 1100°C at 10-14 Torr
Chemical StabilityInert, non-toxic, corrosion resistant

Material Specifications

Molecular Weight160.08
Density4.8 g/cc
Hardness1.0 on Mohs Test
Electrical PropertiesHas semiconductor properties

Microsurface Corporation is open for business, though at a limited capacity

The US Department of Homeland Security has deemed certain types of businesses as “essential” businesses. Microsurface Corporation is one of the businesses deemed as “essential” based on supporting customers in “Critical Infrastructure Sectors” as determined by the federal government. These sectors include: Critical Manufacturing; Government Facilities; Nuclear Reactors, Materials, and Waste; Defense Industrial Base; and Communications.

We are committed to the safety and health of our employees, our community, and our customers. All office and supporting staff will continue to work from home and shelter in place. Those who are required to come into our facility will make all possible efforts minimize to contact with one another while they work through this pandemic.

To that end, please keep in mind that we are currently running with limited staff and shorter hours. For fastest response please contact us directly by email at info@ws2coating.com or call (408) 723-0700 to check current status.

Our staff is working diligently to process all current or previously delayed orders and move forward with new orders.

Thank you for your patience and understanding during this difficult time.
-Brian Geranen, President