Graphite Lubricant

Graphite is a form of carbon, which is silverycomposite anti-friction coatings and form the
black in colour. Graphite is one of the predominantsecond phase particles of metal based composite
materials used as solid lubricant. The lamellaranti-friction coatings. They are used as molds for
structure of graphite (the tendency to flake), incontinuous casting and solid lubricant in metal
the form of dry powder, makes it ideal to reduceforming.
friction. Graphite can also serve as a liquid basedGraphite is also used in continuous casting molds.
lubricant. The lubrication film provides resistance toThe molds are fabricated from iso-statically
wear and tear and also seizure resistance.pressed graphite. The low friction between the
As a dry lubricant, the powdered graphite reactsmold surface and solidifying metal ensures smooth
with water vapour and the molecular bondingextraction of the casting. The crystal structure of
does not occur, leaving it dry and slippery.graphite provides low friction without the
However, it does not bond well with the surfacerequirement of additional lubrication.
and thus keeps falling off, increasing the need toGraphite is characterized as natural and synthetic.
be applied often. Solid graphite lubricant is tolerantNatural graphite is derived from mining. The
to temperatures of about 900 degree F. Higherrefined graphite contains carbon, sulfur, SiO2 and
temperatures than this causes oxidation ofAsh. The crystallizing quality of graphite is
graphite.determined by the higher content of carbon, and
The liquid graphite lubricants are of differentbetter the lubricity and resistance to oxidation.
types. The graphite grease is designed to stick toSynthetic graphite is sintered from high
the surface, where the grease will prevent thetemperature and has very high carbon content of
graphite from falling off the work surface.up to 99.5-99.9%, and is therefore very good as
Another combination with liquid base is such thata lubricant.
the liquid will evaporate when the mixture isWhile the conventional automotive oils cannot
painted on the surface, leaving the graphite towithstand the high temperatures, graphite can
work to reduce friction.serve as lubricants in automotive engines which
As a dry lubricant, graphite can be used in certainreach temperatures as high as 1,250 degree F.
situations where wet lubricants may cause hazardThe commercially available graphite lubricants are
as in electrical fittings or when lubricatinga colloidal dispersion of billions of microscopic
substances such as wood. Also, graphite greaseparticles of graphite. When this is added to the
can tolerate more heat than natural grease orcrankcase of an engine, it works with the motor
other lubricants.oil to reduce friction. It also penetrates effectively
Graphite may be used as an additive in lubricatinginto areas where oil cannot reach, keeps oil from
oil to increase the thermal tolerance. They arethickening, improves compression and helps
also used as components of polymer basedenergy consumption and fuel economy.