The parts are made from mixtures of coke and graphite powder bonded with carbon. The proportions and types of these materials are selected to obtain the lubricity and wear resistance required in the finished component. The carbon binder is derived from coal-tar pitch or synthetic resins chosen for their high coking yield. The mixture is then formed by compression molding or warm extrusion. The resulting baked carbon part contains interconnected pores, which are usually impregnated with resins, fused salts, glasses, or molten metals.
Impregnation enhances physical properties and can also reduce rubbing friction and wear rates.
Most manufactured carbon parts require some machining to produce required tolerances. Only the hardest carbide or diamond-tipped tools can be used for some grades. Because of this, the larger U.S. carbon producers offer machining service for producing parts to customer specifications.