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Internal combustion engines have been developed for over one hundred and twenty years and are a very mature technology. Over this time, significant improvements in power density and brake thermal efficiency have been realized from improvements in design, processing and material properties. Huge advances in computer simulation capability over the past thirty years have enabled the former two categories to be explored and exploited very thoroughly, leaving materials specifications as the fundamental key to unlocking further efficiency gains. This paper summarizes the design advantages of a range of alternative materials developed for piston, ring connecting rod and bushing applications. A Ford Ecoboost 2.3l RS engine was selected as a baseline engine and the reciprocating parts were re-designed to take advantage of the improved characteristics of these materials.

Engineered materials have made a breakthrough in a quest for materials with a combination of custom-made properties to suit particular applications. One of such materials is 2124/SiC/25p, a high-quality aerospace grade aluminium alloy reinforced with ultrafine particles of silicon carbide, manufactured by a powder metallurgy route. This aluminium matrix composite offers a combination of greater fatigue strength at elevated temperatures, lower thermal expansion and greater wear resistance in comparison with conventionally used piston materials. The microscale particulate reinforcement also offers good formability and machinability. Despite the benefits, the higher manufacturing cost often limits their usage in high-volume industries such as automotive where such materials could significantly improve the engine performance. This paper presents mechanical and forging data for a lower cost processing route for metal matrix composites.