The scientific definition of a ceramic material is an inorganic compound that contains at least one metallic and one nonmetallic element. This definition contains within it a whole world of materials, with different features and behaviors. Some features of ceramic materials are considered the best: high temperature resistance, low deformation under the operation of forces, corrosion resistance, abrasion resistance, and electrical conductivity which can be controlled. Under certain conditions ceramics can be transparent and very strong. The limited resistance of most ceramics to crack propogation impedes their use as structural materials, and this is a major point of research. However, ceramics have extended applications as functional materials.
Small changes in the composition of a ceramic material can significantly alter its properties. As more ions are added and the crystal becomes more complex, the compound will have various electrical, magnetic, optical, mechanical, and chemical properties. In some cases the crystal structure allows one form of energy absorption and its emission in a different way, so-called energy conversion. For example, turning mechanical energy into an electrical signal or vice versa. A cell phone vibrates or rings through the vibrations of a ceramic material, in which an electrical current at a certain frequency was transferred. The same principle is used for transducers in ultrasonic examinations in clinics and hospitals: the electrical pulse of from an external voltage supply is converted through a piezoelectric crystal (pressure-electricity) into vibrations (mechanical sound waves) which are transferred into the body. These sound waves are scattered and reflected by tissues in the body, are detected and converted back into an electrical signal that is displayed on a screen.
Various research programs in the Department of Materials Engineering deal with the production of special ceramic materials, characterization of their structure, and characterization of their properties. Details on these research programs can be found in the web sites of the following faculty: