Using additives to modify surfaces in a self-repairing way

Using additives to modify surfaces in a self-repairing way 

The traditional life cycle for coatings in most applications begins with the surface-modification process in a manufacturing environment. During use in the field, the coating suffers degradation due to processes such as wear and corrosion, until it reaches the end of its service life. 

In the case of antiwear additives and the so-called extreme-pressure additives, the situation is more complicated the crncial reaction that leads to the production of a wear-protective layer may occur only in the case of high pressure and/or locally high temperatures. The precise modes of action of such additives, which are present in virtnally every lubricating oil, have been the topic of intensive research for several decades (see Chapter 2d). A significant incentive for such research has been the search for alternative additives that are less damaging to the pollution-control devices on modern automobiles. The commonly used zinc dialkyldithiophosphates 

Spencer, Sweet, Hairy, Soft, and Slippery. Science (2008) Vol. 319 pp. 575-576. W.B. Hardy, I. Bircumshaw, Boundary Lubrication, Plane Surfaces and the Limitations of Amon-tons Law. Pmc. R. Soc. Land. (1925) Vol. A108 pp. 1-27. 

Anghel, C.H. Bovington, H.A. Spikes, Mechanisms of Oiliness Additives. Tribology Int. (2000) Vol. 33 pp. 241-247. 

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