Other Bearing Materials

An extensively hard wood of great density, termed as lignum vitae, has been utilized for bearing applications. Along with water like lubricant and cooling medium its antifriction properties and wear are comparable along with those of bearing metals. Lignum vitae has been utlized with satisfactory results particularly in cases of step brings of vertical water turbine, marine service, paper mill machinery and even roll neck bearing of rolling mills.

Further recently, in such cases whereas use of water as lubricant is essential, particularly if sand and grit are present soft vulcanized rubber bearings have been utilized. A soft, tough, resilient rubber acts like a yielding support, permitting grit to pass throughout the bearing with no scoring the shaft or the rubber.

Graphite which is a form of carbon has been utilized as lubricant in bronze bearing however bearing made entirely of carbon are being utilized. At low speeds carbon bearings can carry pressure as high like 6.8 MPa. Natural and Synthetic composite materials, plastic and reinforced plastic are being utilized as bearing material. Though, their characteristics are not well established as till now. Powder metallurgy bushing permits oil to penetrate into the material since of its porosity.