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The reduction of fuel consumption and pollution emissions, the improvement of the engine efficiency as well as the cost reduction in manufacturing and assembly are in the focus of actual research activities in the automotive industry. Most of these requirements can be fulfilled by a reduction of the total vehicle weight. This results in an increasing utilization of light metals for chassis, body and engine components. Significant weight savings are obtained by changing the engine block material from cast iron to aluminum. Due to the harsh operation conditions, the aluminum cylinder must be reinforced. Approaches to increase combustion as well as operation efficiency and lifetime of light metal engines are thermally sprayed APS (Atmospheric Plasma Spraying) and HVOF (High Velocity Oxygen Fuel Spraying) coatings on cylinder liners of the aluminum crankcases. By using this coating technologies, also material combinations containing solid lubricant dispersions can be deposited.

High power diesel marine propulsion engines are subject to long working periods as well as harsh operation conditions. Due to the extraordinary requirements in service and operation, these engines must sustain a long operation life cycle, reliability and availability. In ship diesel engines, wear usually occurs in the top region of the cylinder liner, where the maximum mechanical and thermal load appears. Modern high pressure direct fuel injection engines (i.e. common rail and pump injector systems) in combustion with high rate turbo charging increases the combustion temperature, pressure and flame propagation. Additionally to this extreme thermo mechanical and pressure load, the top region is superimposed by abrasive wear mechanism, due to the high quantity of abrasive particles and carbon depositions on the pistons surface, occurring by the combustion of heavy fuels and oil degradation.

The use of magnesium diecastings for many automotive applications is mainly hindered by the lack of cost effective functional coating systems. For car body applications, e.g. no satisfying coating system is currently available matching Class A surface requirements for exterior car body components. In the first part of this paper a novel multilayer coating system is introduced containing one layer based on silicone-modified organic resins which provides excellent corrosion resistance and an improved leveling behavior. Thus the coverage of different surface defects originating from diecasting is possible without or with only minimum posttreatment like sanding and grinding. Results showing the performance of the novel coating systems in salt spray testing and VDA cyclic testing are presented.

Actual trends with regard to light weight design in the automotive industry, in order to reduce fuel consumption and pollution emissions as well as improve the engine efficiency lead to the increasing use of light weight engine components. Due to the harsh operation conditions, the aluminum cylinder surface must be reinforced, and new techniques have been developed and applied. A very promising technological alternative is the use of HVOF (high velocity oxygen fuel) deposited internal coatings, showing improved coating quality results compared to APS (atmospheric plasma spray) coatings. Several HVOF (High Velocity Oxygen Fuels) coating processes (with different fuel gases/fluids) were compared and studied, with a complete mechanical characterization and evaluation of the coatings. Also an economical comparison for the different coating systems is shown.

Recent automotive engineering developments concerning fuel consumption regulations and decreasing material and manufacturing cost result in an increasing utilization of light metal components for automotive applications. Significant weight savings are obtained by changing the engine block material from cast iron to aluminum. Since all parts of a combustion engine interact as a system, the individual components must sustain the combustion pressure and temperature as well as wear and friction effects of moving surfaces in different environment and lubrication. Approaches to increase combustion as well as operation efficiency and lifetime of light metal engines are ceramic and cermet coatings on the cylinder liners of die casted aluminum crankcases. Such functional and protective thermally sprayed coatings on cylinder bores include material combinations with solid lubricant ability.