Self-lubricating composites composition

Lubricants. TeUurides of titanium, 2irconium, molybdenum, tungsten, and other refractory metals are heat- and vacuum-stable. This property makes them useful in soUd self-lubricating composites in the electronics, instmmentation, and aerospace fields (see Lubrication and lubricants). Organic teUurides are antioxidants in lubricating oUs and greases. 

Obtain specific properties using, for example, a self-lubricating composite insert. Discontinuous fibre reinforced thermoplastic composites can also be overmoulded onto GMT sheets. 

Tsuya, Y., Shimura, H. and Matsunaga, M., A Study on Some Metal-Base Self-Lubricating Composites Containing Tungsten Disulfide, Lubric. Eng., 29, 498, (1973). 

Gardos, M.N. and McConnell, B.D., Development of a High-Load, High-Temperature Self-Lubricating Composite - Parts I to IV, Proc. ASLE-ASME Lubrication Conference, New Orleans, LA, (5-7 October, 1981). ASLE SP-9. 

Lavik, M.T, and Hopkins, V., Development of Self-Lubricating Composites Utilising Carbonised Phenolic Matrix, AFML-TR-75-175-PT. (1975). 

Suzuki, M., Moriyama, M., Mishimura, M. and Hasegawa, M, Friction and Wear of Self-Lubricating Composites at Temperatures to 450 in Vacuum, Wear, 162-164, 471, (1993). 

Wu, Y., Wang, F., Cheng, Y. and Chen, N., A Study of the Optimization Mechanism of Solid Lubricant Concentration in Ni/MoSj Self-Lubricating Composite, Wear, 205, 64, (1997),... 

Boes, D.J. and Bowen, P.H., Friction-Wear Characteristics of Self-Lubricating Composites Developed for Vacuum Service, ASLE Trans., 6, 192, (1963). 

An inorganic solid lubricant has been described as a self-lubricating composite comprising a chromium oxide (e.g. chromic oxide, Cr203), a metal binder comprising Cr/Ni or Cr/Co alloy, a metal fluoride, and, optionally, a metal lubricant [60]. A milled powder mix of the composite is deposited onto a substrate, e.g. by plasma spraying. 

Dellacorte, C., Edmonds, B.J. (1999) Self-lubricating composite containing chromium oxide. US Ratent 5,866,51. 

Table 19-23 lists substances which have been studied seriously as components of self-lubricating composites. The matrix materials contribute properties such as mechanical strength, resistance to corrosion, etc. The function of a polymeric plastic such as polytetrafluoroethylene... 

Development and tribological evaluation of these self-lubricating composites over the past several years has recently been reviewed by Sutor and Gardos (7, 8). This work demonstrated that many of the composites which were excellent lubricants for steel were poor lubricants for silicon nitride. Thus, achieving effective solid lubrication of silicon nitride was of particular concern. 

Gardos, M. N. McConnell, B. D. "Development of a High-Load, High-Temperature, Self-Lubricating Composite," American Society of Lubrication Engineers SP-9, 1982. 

Wear-Resistant, Self-Lubricating Composition. Japan Patent Application 58-109554. 

IHbo/Comp, Self-lubricating composites, Tiodize Co. Inc... 

S-Q.Niu, J-R Zhu and J-L.Quyang, Study on Development and Properties of Several New Type High Temperature Self-lubricating Composites, Tribology (In Chinese), No 4 (1995)15. 

Whereas the traditional dimethyl siloxane fluids provide very poor lubrication for steel on steel and other common metals, thin films on glass reduce handling damage, small amounts in plastic composites bleed to the surface for self-lubrication, and they provide a superior lubricant for mbber surfaces. 

Figure 5.21 displays the reinforcement of a bush with an inner unidirectional composite insert. The principle is the same for a bush with a self-lubricating insert. 

Combination of metal to be deposited with water repellent powder. In composite plating, the characteristics of particles to be codeposited are the most important. Water repellent fluoroplastic powder represented by Polytetrafluoro-ethylene (PTFE) has various unique and interesting characteristics such as non-adhesiveness, self-lubricity and chemical resistance, as well as water repellency. Incorporation of such powder into the composite plating would give a surface with quite different characteristics from those obtained by conventional surface treatments. Representative water repellent powders used in this study of composite plating are graphite fluoride [(CF) ] and PTFE. 

The two purposes, of lubricant supply or friction reduction, are of course not entirely distinct, since continuing friction reduction requires a continuing supply of lubricant. The difference lies in the fact that the amount of lubricant required to maintain low friction of the composite itself is relatively small, probably restricted to a film which may be only a few molecules thick. The more general lubrication of a bearing system will require an additional supply of lubricant which is at least sufficient to provide an equivalent film on all the bearing surfaces involved. With the inevitable wastage inherent in movement of lubricant to other surfaces, the lubricant demand will be much greater than for self-lubrication alone. 

As a result, those workers who are trying to develop self-lubricating materials for these high temperatures are looking at much more exotic and much less efficient lubricants, such as the calcium fluoride/barium fluoride eutectic and silver used in the NASA PS200 and PM212 high-temperature composites ... 

Betts, S., Dackow, J. and Murray, S.F., Performance Characteristics of Self-Lubricating Polyimide Composites, Proc. 2nd ASLE Inti. Conf. on Solid Lubrication, Denver, Colorado, (15-18 Aug. 1978), ASLE SP-6, p. 195. 

DellaCorte, C. and Sliney, H.E., Tribological Properties of PM212 A High-Temperature Self-Lubricating, Powder Metallurgy Composite, NASA TM-102355, (1990). 

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