This post discusses properties, applications, methods of application, and conditions in which these film lubricants are applied.

1. Characteristics and
Applications of Dry Film
Coatings

2. Dry film lubricants, alternatively known as solid film lubricants, are lubricating
substances that are used to reduce friction between two sliding surfaces. Some of
the popular dry film lubricants are graphite, molybdenum disulfide (MoS2),
tungsten disulfide (WS2), and PTFE. They form a tough coating over the part
and inhibit corrosion. This post discusses properties, applications, methods of
application, and conditions in which these film lubricants are applied.

3. General Properties of Dry Film Lubricants
• MoS2 and WS2 are oilioscopic, which means they cannot tolerate detergents.
• Graphite has high environmental and oxidation temperatures.
• MoS2 and WS2 can tolerate high loads, and perform well in a vacuum.

4. Conditions In Which Dry Film Coatings Are Applied
• Reciprocating Motion: A typical application with reciprocating motion
depends on a reliable lubricant to minimize wear and tear. Liquid lubricants
may lose their ability to maintain a proper lubricating film in extreme
conditions such as high pressure or temperature. However, dry or solid
lubricants don’t migrate, and they help avoid galling, seizing, fretting and
corrosion.
• Extreme Environments: Most dry film coatings can perform at high
temperatures, pressures, speeds and other extreme environments. In some
cases, liquid lubricants may fail under such conditions. For example –
semiconductor manufacturing or high altitude/space applications cause
evaporation of typical organic oils and greases. Also, in dry and dirty
applications, dry film lubricants will not attract dirt and dust which will create a
gummy and abrasive mixture with oil and grease.

5. Conditions In Which Dry Film Coatings Are Applied
• Typical Surfaces: Solid film lubricants are used on all types of surfaces.
Bearings, pistons and cylinders, gears, fasteners, pins, injection mold
components and many more. Anywhere where long term lubrication and
extended service life is beneficial, dry film lubricants can be beneficial.

6. Methods of Application
Brushing/Spraying/and Dipping: Solid film lubricants can be added to specified
resins and binders. These lubricants are applied to the specified components, which
are often inaccessible to lubrication after assembly. Depending on the base material
of the component, various air cure and thermal cure products are available.
Specifications for this type of coating include MIL-PRF-46010, AS5272, MIL-L-
23398 and more.
Impingement Coatings: These are anti-friction coatings, typically molybdenum
disulfide (MoS2) and tungsten disulfide (WS2) that can be applied at room
temperature and do not require a curing process. These are thin coatings, < 0.0001”,
that typically do not effect normal machine tolerances. They can work as the sole
lubricant and also work well with hydrocarbon based oils and greases. Specifications
for this type of coating include AMS2526, AMS2530 and DOD-L-85645
Composites: Generally, solid film lubricants can be alloyed into polymers and
sintered materials for improving certain properties.

7. Applications of Dry Film Lubricants
There are a variety of applications for dry film lubricants. Many of them are used in
automotive, aerospace, and transportation industries. Below are some of the popular
applications of dry film lubricants
• Gears
• Pistons
• Plastic Moulding Parts
• Combustion Engines
• Processing Equipment
• Connectors and Couplings
• Cables, Fasteners, and Slide Mechanisms

8. The choice of the right dry film coating will depend on your application
requirements, operating temperatures, pressures and environment. Consult with a
lubrication engineer to decide which lubricant will suit your application.
Micro Surface Corporation
270 Hillsdale Avenue San Jose, CA 95136
Phone: +1 408 723 0700
Fax: 408.723.0710
E-mail: info@ws2coating.com
https://www.ws2coating.com/