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Aluminum is the material for lighter structural components, and is also advantageous for the purpose of heat transfer. The automotive powerplant requires an efficient material with less weight and proper thermal characteristics, as demanded by early aviation applications, due to the recent necessity for environmental and energy conservation. However, cast iron has been the dominant material used for engine blocks because of simple economic reasons. To overcome the simple cost disadvantages of aluminum engine block application, it is necessary to utilize the full potential of the material to the proper advantage. New aluminum engine blocks with a unique cooling system of air assisted water cooling were developed. The basic design concept between cast iron and aluminum are the same, except for the design differences due to the structural stiffness of both materials. However, there are thermal property differences between aluminum and cast iron other than stiffness and weight.

There are two analytical methods for optimizing automotive structural dynamic characteristics to improve vehicle ride quality and minimize structural mass for improved fuel economy. The first method, the traditional approach, is to move the undesired structural resonant frequencies out of the range of the forcing functions by modifying the mass and stiffness parameters appropriately. However, in some cases the resonant frequencies are insensitive to parameters; these cases normally are difficult to improve. Fortunately, there is a second method, based on the natural phenomena that an anti-resonance exists for each resonant frequency. Furthermore, the sensitivity of these anti-resonance nodes to the structural parameters of mass, stiffness and damping are uniquely different. It is this difference in sensitivity that permits cases to be solved, which resist solution by the traditional first method.

This is a descriptive review of the ceramics structural applications developed by Isuzu, Mazda, Nissan, Toyota and General Motors in spark ignition, Diesel and gas turbine automotive engines; new analytical procedures needed for the design of structural ceramics; new silicon nitride ceramics with strength of material properties approaching steel; new ceramics processing techniques which have been reduced to commercial practice in Japan on a mass production scale; and tests of vital structural components fabricated of these ceramics.