Self-lubricating properties

Carbon-graphite 700 Good bearing and self-lubricating properties. Good resistance to chemicals, beat. 

Teflon has self-lubricating properties which are utilized in making nonstick frying pans and lightweight bearings. 

Ruorinated thermoplastics are only used for high-performance applications related to their high heat, low temperature, chemical inertness, high purity, non-stick and self-lubricating properties. High-purity grades are appreciated by the semiconductor, pharmaceutical and other similar sectors. 

Lubricant-film bearings primarily employ the white-metal babbitts, and a variety of copper and aluminum alloys. Since steel and cast iron structural parts are frequently used as oil-film bearing materials, they are also briefly covered along with silver, zinc, and cadmium which find limited use. For small bearings and bushings in light-duty and intermittent service, materials with self-lubricating properties are commonly used. 

The product ( Teflon ) is a solid, chemically inert substance that is stable to around 300°. It makes excellent electrical insulation and gasket materials. It also has self-lubricating properties, which are exploited in the preparation of low-adhesion surfaces (such as nonstick fry pans) and light-duty bearings. 

Mizutani, Y., Shimura, Y. and Nagasawa, Y., Self-Lubricating Property of Fe-Mo-S Alloys in Vacuum, Proc. 3rd Inti. Conf. on Solid Lubrication, Denver, Colorado, (7-10 Aug. 1984). ASLE SP-14, p. 152. 

Powdered cellulose has been used as a direct compression diluent. Though it forms hard tablets, fluidity is poor and dilution potential is low. Like microcrystalline cellulose it has some self-lubricating properties, but addition of a lubricant is usually necessary, causing a marked reduction in tablet strength. ... 

Nylons are used in applications requiring durability, toughness, chemical inertness, electrical insulating properties, abrasion and low frictional resistance, and self-lubricating properties. Table 15.13 lists markets and typical applications of nylons. In many of these applications, nylons are used as small parts or elements in subassemblies of the finished commercial article. 

Polytetrafluoroethylene (PTFE), also known by its generic DuPont tradename of Teflon, is a linear polymer that has a molecular structure similar to PE, but with all the hydrogen-atoms replaced by fluorine atoms (CE2-CE2) . Since fluorine-atoms prefer contact with fluorine-atoms, while repelling all others, this repulsion reduces the friction coefficient of the system and produces a non-adhesive surface (with self-lubricating properties). The strong C-C and C-F bonds make PTFE chemically inert, with excellent chemical resistance. 

Porous bronze bearings are available, made from powdered metal. The powder is pressed into shape leaving air spaces or pores. When the bearing is subsequently immersed in oil, these pores absorb oil. In operation, the oil seeps from the pores to provide an oil film which prevents metal-to-metal contact. Alternatively, graphite can be incorporated in the initial powder to provide a self-lubricating property. 

Because of the free graphite it contains, cast iron has certain self-lubricating properties but requires additional lubrication as there is a tendency for the material to pick up and quickly seize. 

Other properties that can be affected with the proper choice of fillers for a specific application include compressive strength, adhesion, arc and tracking resistance, density, and self-lubricating properties. 

Multiwalled carbon nanotubes (MWCNTs) were proven to also contribute to the increase in the wear resistance and to the reduction of the friction coefficient in modified BMI resins (Liu et al. 2007a), especially when MWCNTs are functionalized with carboxylic groups. This is because they induce a change in the main wear mechanism—from adhesive wear in neat resin to abrasive attrition—by changing the self-lubricating property of the worn surface, the dispersion of filler in the matrix, and the interfacial adhesion between filler particles and matrix. 

The applications for hard particle composites He, for example, in internal combustion engines, textile machinery and gas turbine compressors, where combined properties can include resistance to wear, fretting, scuffing and heat and chemical attack. The softer particles display an advantageously low coefficient of friction and effective self-lubricating properties. 

Fig. 8.21 Electroless tiickel-PTFE deposition, (a) The deposit contains up to 23% by volume of PTFE as dispersed particles. The deposit has a typical composition of Nj 87%-P 7%-PTFE 6%wt. (b) Engineering applications utilize the low-friction corrosion resistance and self-lubricating properties. In addition to the threaded and grooved components shown, examples include bait and butterfly valves, pistons and moulds for plastics or rubbers. (Courtesy Ionic Surface Treatmenti. lonlube coatings by Dudley Division.)...

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