Development of high temperature aluminum alloys for automotive diesel engine applications

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This project proposal is for the development of new aluminum alloys with improved high-temperature performance (creep resistance, strength, ductility, thermal fatigue resistance and castability) as well as acceptable cost to be used in automotive Diesel engine applications for vehicle weight reduction and environmental benefits. The Diesel engine, introduced by Rudolph Diesel in 1892, achieves self ignition via fuel injection into air which is already compressed in the combustion chamber. Compared to gasoline engines, the Diesel achieves a higher combustion ratio and higher fuel efficiency. The Diesel has 30%lower CO2 emissions per mile and is considered one of the most viable environmentally friendly technologies for vehicles. Market penetration of the Diesel in Europe shows substantial growth since 1991 reaching 50% (70% in France) market share; while in North America it sees slow acceptance (1% cars and 4% light trucks) due to past experience with older technologies and sulfur-containing fuel usage. However, "clean Diesel" using lower sulfur content fuel has become available since 2006. US Environmental Protection Agency (EPA) considers the Diesel an extremely attractive technology to help achieve EPA's future standards. Tax incentives ($3500 credit) for buyers of new Diesels are offered in the US since April 2006. Currently, the Diesel engine and cylinder head are mostly cast iron due to the high compression pressures and temperatures occurring in Diesel operation. Further weight reduction via Al substitution would result in substantial fuel economy and increased environmental benefits. 10% saving in vehicle weight leads to 6-8% fuel economy which translates (during the life time of a car) to 17-20 kg reduced emissions of CO2, per kg of vehicle weight reduced. Only a small portion of the diesel is aluminum and the increasing torque requirements in newer common rail turbo diesels necessitate new alloys with improved performance under thermal fatigue conditions. In this project novel aluminum alloys will be developed to meet the requirements of the Diesel technology.