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In this work, the design and testing of a silicon-nitride (Si3N4) piston-cup for a Petter AV1 laboratory diesel engine is presented. A preliminary design was first prepared and tested for thermal shock. The tests showed that non uniform displacements occurred between the ceramic plate and the piston. An improved design was then prepared, which allowed control of the characteristics of the gasket mounted between the ceramic plate and the piston. This second design was evaluated by thermal shock and exposure to cyclic pressure variation, followed by engine tests. A short description is given of the experimental set-up used for investigating the ceramic materials which are candidates for the moving parts exposed to thermal and dynamic shock in internal combustion engines. Finally two pistons with ceramic top plates were introduced in the engine with thermocouples mounted at different points of the liner and exhaust valve.

The objective of this work was to demonstrate the possibility of adding a 3% methanol blend to the normal gasoline for the existing vehicle population in the climatic conditions of Israel. The fleet test was performed with the help of three public stations in which the methanol gasoline blend is sold to the general public on a voluntary basis. After ten months of operation with a sample of over 14000 vehicles the results are very encouraging and the acceptance of this blend among the drivers is very good. The extending possibility of adding a 3% methanol blend to the normal gasoline in all the public filling stations in Israel is the principal conclusion of this work.