ultra-hard, low-friction coating is slicker than Teflon®
Asked Questions About Near-Frictionless Carbon Films
Description of Technology
Key Features of New Carbon Film
Projected Benefits and Industrial
Is Near-Frictionless Carbon Suitable for Your
A new, ultra-hard carbon film that we
call near-frictionless carbon (NFC) provides friction coefficients of
0.001 or less when tested in a clean environment; i.e., dry nitrogen or
argon. Other known or inherently low friction materials -- such as MoS2,
Teflon™, smooth diamond and diamond-like carbon films, or natural diamond
-- provide friction values of 0.02 to 0.15 under the same test conditions.
A steel surface well lubricated by a 10W30 motor oil gives a friction
coefficient of 0.12, while an unlubricated surface has a friction
coefficient of about 0.8. The friction coefficients of new carbon films in
air are in the range of 0.02 to 0.06 which still are very good for dry
Another interesting feature of new
carbon film is that it provides extremely low wear rates (i.e., 10-10 -
5x10-11 mm3/N.m; 100 to 1000 times lower than those of the materials and
coatings mentioned above) when sliding against steel or ceramic materials.
The wear rate of a well lubricated steel surface is 10-7 mm3/N.m, while
that of an unlubricated steel surface is about 10-5 mm3/N.m. It looks that
the friction coefficient of Argonne's NFC film is perhaps the lowest
reported to date for a solid material and its wear resistance is the
highest. In terms of durability, the film has an extremely long endurance
life. In a recent test, we accumulated over 14 million sliding cycles
without wearing through. This film was about 1 micrometer thick and
deposited on a H23 steel and was tested under dry sliding conditions and
in a clean test environment. Combination of these qualities makes this
carbon film unique and potentially useful for a wide range of
applications. The film can be deposited at room temperature on any kind of
substrate (i.e., metals, ceramics, and polymers) and at fairly high
Because of its extremely low friction
coefficient and wear rate, the new NFC film offers a way to make rolling,
sliding or rotating machine parts more efficient and long-lasting. As
mentioned above, the NFC films reduced friction by factors of 20 to 100
below the levels feasible with existing low-friction materials, coatings,
or lubricants. In aerospace and transportation systems, such reduction in
friction translates directly into higher efficiency and better/quieter
performance, while less wear results in longer lifetime and lower
maintenance cost. Therefore, the key advantages expected from these carbon
films in moving mechanical assemblies are extended wear life, reduced
maintenance costs, improved reliability, reduced environmental emissions,
and most importantly increased energy efficiency resulting from decreased
Since its first observation, we have
been extremely busy exploring the ultra-low friction and wear mechanism(s)
of the NFC films. Accordingly, we did not know much about potential
commercial uses of this coating, but a news release by Argonne in October
1997 has generated an overwhelming interest from industrial companies.
Argonne's NFC film has also been featured in a number of scientific
journals that are still generating interest in this new material. Argonne
currently is working with three private firms to develop
near-frictionless carbon coatings to increase engine efficiency, extend
wear life and reduce maintenance costs for motor vehicles (more .
. .). Certain components in engines operate under marginally
lubricated conditions and are subject to very heavy loads causing existing
materials and coatings to fail. It is hoped that a hard and slick coating
on the sliding surfaces of these critical engine components will enable
the realization of long-lasting and highly fuel efficient engines.
While this CRADA, along with our
commitment to explore the ultra low friction and wear mechanisms of the
NFC films, will keep Argonne's research team busy, Argonne anticipates
that the uniqueness of this new material may lead to its use in a variety
of commercial applications and Argonne is interested in finding ways to
get this near-frictionless carbon film more widely studied and evaluated.
Carbon Suitable for Your Application?
Argonne is interested in finding
partners to help develop applications for this material, but we have
received a large number of inquiries, and it is impossible to adequately
follow up on all of them. To help our technical staff make properly
evaluate the suitability of this new material to your specific area of
interest, we would appreciate your response to the following:
- Describe your application(s)
- What are your technical
requirements or specifications -- temperature, environment, loads,
shapes, substrates, etc.
- Economic considerations -- what's
required to be competitive?
- Estimated market size -- area to be
coated, number of pieces per year, etc.
- What are you using now?
- What are the primary deficiencies
with your current approach? What problems do you need to solve?
- Have you looked at other carbon
coatings or diamond-like coatings? Which ones? How did they work?
- Is there anything else it would be
helpful for us to know?
Please send your response to Donald
Knight, Office of Technology Transfer, Argonne National Laboratory, 9700
South Cass Avenue, Argonne, IL 60439. You may also fax your response to
630/252-5230 or email it to email@example.com.
For More Information
Test samples of the NFC coating are
available. For information on licensing, obtaining samples and
collaborative arrangements, contact Argonne's Office of Technology
Transfer (800-627-2596, firstname.lastname@example.org).