Graphite is a sort of carbon, which is silvery black in colour. Graphite is one of the predominant materials used as solid lubricant. The lamellar structure of graphite ( the inclination to flake ), in the guise of dry powder, makes it ideal to reduce friction. Graphite can also serve as a liquid based lubricator. The lubricating film provides resistance to damage and also episode resistance.
As a dry lubricator, the crushed graphite reacts with water vapour and the molecular bonding doesn't happen, leaving it dry and greasy. However , it does not bond well with the surface and so keeps falling off, increasing the necessity to be applied frequently. Solid graphite lubricant is long suffering to temperatures of roughly 9 hundred degree F. Higher temperatures than this is the cause of oxidization of graphite.
The liquid graphite lubricants are of different types. The graphite grease is intended to stick to the surface, where the grease will forestall the graphite from falling off the working surface. Another mix with liquid base is specifically so that the liquid will vaporize when the mixture is painted on the surface, leaving the graphite to work to reduce friction.
As a dry lubricator, graphite may be employed in certain situations where wet lubricants may result in jeopardy as in electric fittings or when lubricating substances like wood. Also , graphite grease can put up with more heat than natural grease or other lubricants.
Graphite may be utilised as an additive in lubricating oil to increase the thermal tolerance. They are also utilized as parts of polymer based composite anti-friction coatings and form the second phase particles of metal based composite anti-friction coatings. They are employed as molds for continuing casting and solid lubricant in metal forming.
Graphite is also used in constant casting molds. The molds are fabricated from iso-statically pressed graphite. The low friction between the mould surface and solidifying metal makes sure smooth extraction of the casting. The crystal structure of graphite provides low friction without the requirement of further oiling.
Graphite is characterized as natural and manmade. Natural graphite is derived from mining. The refined graphite contains carbon, sulfur, SiO2 and Ash. The crystallizing quality of graphite is decided by the higher content of carbon, and better the lubricity and resistance to oxidization. Man-made graphite is sintered from high temperature and has particularly high carbon content of at least 99.5-99.9%, and is so superb as a lubricant.
While the conventional car oils can't withstand the raised temperatures, graphite can serve as lubricants in auto engines which reach temperatures as high as 1,250 degree F. The available graphite lubricants are a colloidal dispersion of many billions of microscopic particles of graphite. When this is added to the crankcase of an engine, it works with the motor oil to reduce friction. It also penetrates effectively into areas where oil cannot reach, keeps oil from thickening, improves compression helping energy consumption and fuel usage.
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