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Worldwide emissions standards are becoming increasingly rigorous, and this leads to more complex engine demands. Several new PCU (Power Cell Unit) technologies are being applied to cope with these demands. This means engine parameters are changing, e.g. higher EGR (Exhaust Gas Recirculation) rates, higher PCP (Peak Cylinder Pressure), lower viscosity oils, higher oil contamination and soot. Therefore the operating conditions for the bearings have drastically changed, leading to an environment prone to seizure occurrences. There is a clear demand for seizure resistant bearings motivated mainly by the increased engine complexity described above. Therefore for HDD (Heavy Duty Diesel) applications the PCU robustness should not be compromised also in terms of wear and fatigue resistance. The polymeric coating developed by MAHLE was applied over a sputtered layer and has demonstrated to be a suitable solution to attend to the application demands.

The demand for higher output performance engines has lead to the increase of PCP (Peak Cylinder Pressure) and more aggressive engine designs for cylinder liners, mainly for new heavy duty engines developments where low cost components are been introduced. Such trends have generated demands to adequate the liner design by improving its material properties by changing its chemical composition, new materials data or even by introducing more accurate casting manufacturing process. Therefore, there is a clear tendency to development more and more alternative solutions that combine a certain technical high-value added and low cost. The most important material properties for cylinder liners are the ultimate tensile strength (UTS) and the fatigue tensile strength. Both parameters confer to the cylinder liners, especially for wet top flanged designs, the ability to survive under high mechanical and thermal load conditions even with reduced wall thickness.