Industrial use of plasma-deposited coatings for components of automotive fuel injection systems

Modem fuel injection systems for cars consist of precise mechanical parts, which need solid lubricant coatings to be protected from friction and wear. Diamond-like-carbon (DLC)-coatings show crucial advantages in a low wear (see the high hardness), in the low coefficient of friction (even for a non-lubricated contact with steel as a counterpart) and in the low wear of the counter body. Several examples of applications of DLC-coatings are discussed. Model wear tests like the oscillating wear test are suitable for various tribological applications like piston in a cylinder or valve lifter on a camshaft. To get a reproducible contact between the two parts in a tribological contact, a running-in process for the oscillating wear test was developed. In order to design powerful systems and find cost-saving solutions shortly, coatings should be used as constructional elements for mechanical systems. The integration of coatings into the modeling and simulation of precise mechanical systems will be discussed for an application with impact wear. The importance of surface engineering as the application-specific design of the surface (with a coating) and the component-part as a system with high performance in the interaction with the surroundings will be emphasized. (c) 2005 Elsevier B.V. All rights reserved.