Intelligent handling of our limited energy resources and the demand to reduce emissions are today the main drivers for developing efficient combustion engines. Therefore slide bearings and also other parts of the powertrain are facing major challenges caused by: Significantly increased operating pressure, temperature and sliding speed as well as the use of new lubricants and fuels. Furthermore, a ban of hazardous elements (e.g. lead, cadmium) in the applied materials is looming. With respect to above mentioned facts, the mechanical and tribological boundary conditions for bearings in future engines are subjected to change immensely. These changes can only be met by new lining materials and bearing types. From the standpoint of strength, the main critical factors are the soft phases — mainly tin and lead — added to both aluminum and copper based bearing alloys to obtain the necessary tribological behavior. Soft phases are limited in their temperature stability and in addition, lead is an environmental critical element and is restricted. For upcoming engine generations even novel aluminum-tin alloys will reach their performance limits and the classical leaded-bronze material as basis for tri-metal and sputter coatings can no longer cope with the life-time expectations. In addition, corrosion issues will come up due to new oil additives in truck and high speed engines. The present paper proposes, for the application in high speed and truck engines, new slide bearing types with appropriate characteristics and the desired performance required by engine designers: A high strength, thermally stable aluminum alloy with excellent mechanical properties by using re-crystallization inhibition mechanisms; a series of new solutions on the basis of a lead-free bronze linings having brilliant thermo-mechanical process capabilities resulting in high strength properties. Adequate tribological behavior is gained by combination of the new lining alloys with different surface layers. Fundamental working principles, development work and first application results of the new bearing types are presented in relation to existing solutions.

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