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Engine development activities are being driven forward primarily by the challenge of continuing to reduce CO2 and exhaust emissions. From the piston/liner system it is well known that Lube Oil Consumption (LOC) is affected by the bore distortion occurrences within Internal Combustion Engines (ICE) that usually demands a redesign on the piston ring pack not in favor to reduce friction losses. This article shows a potential solution to reduce bore distortion and oil evaporation through more efficient heat dissipation from combustion chamber to engine cooling system in a modern aluminum Spark Ignition (SI) block. Electroplated nickel coating applied to the external cast iron surface previous to the casting process enable a metallurgical diffusion layer with the aluminum block material and therefore improve heat conductivity in fired operation conditions compared to conventional cast iron liners.

With the implementation of Proconve P7, several challenges were faced regarding the integrity of the Power Cell Unit (PCU), which comprehends pistons, rings, cylinder liners, pins, conrods and bearings. The technologies of reducing NOx affect directly the performance of these parts. The systems focused on EGR (Exhaust Gas Recirculation) provoke a higher level of soot contamination in the oil, which creates to all the PCU an abrasion mechanism that leads to the increase of wear load. The systems focused on post treatment of the exhaust gas enables to reach higher PCP (peak cylinder pressure) and higher temperature of combustion. Such conditions are also critical to the PCU combustion, which needs to increase resistance to higher mechanical and thermal loads. Using the experience of Europe and NAFTA some expectations about the environment conditions of Heavy Duty Diesel (HDD) engines after Proconve P7 can be discussed.

The tendency to use aluminum alloys to replace conventional gray cast irons (GCI) materials in engine blocks of passenger cars is gaining more and more importance driven by reduction of engine weight to achieve expectation for lowering fuel consumption and CO₂ emissions. Cast-in cylinder liners are commonly applied inside of aluminum engine blocks with designs of the outer surface usually selected through analysis of the aluminum casting process (e.g., high pressure die casting, precision sand cast), geometry complexity, thermal and mechanical loads. A good quality of clamping (bonding and shear strength) between the cast-in cylinder liner and aluminum block might guarantee a reliable heat transfer and thus low bore distortion. The good clamping can also contribute to improve the final machining of the liner after block casting. The most effective variants of cast-in cylinder liner designs were selected for the evaluation of clamping performance.

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.