Ceramics for Transportation Engines—Siren or Solution

The major challenges facing transportation engines—shrinking resources, preserving the environment, and competition—are reviewed and the promise of new materials, specifically ceramics, in helping to meet these challenges is discussed. As a background for understanding the properties of materials, the structure of materials (first at the subatomic level, then the molecular level, and finally at the mircostructure level) is reviewed. The relationship of this structure to properties of ceramics judged to be of importance to engines is then presented. The effect of these properties on engine performance such as volumetric efficiency, fuel economy, heat rejection, inertia, friction, wear, fuel tolerance, and packaging are discussed. It is concluded that ceramics have special properties that, for selected applications, are already justifying their use in transportation engines. It is further concluded that these special application uses will continue to grow and precede general use of ceramics for in-cylinder insulation aimed at improving fuel economy.