Cutler, Ivan B.
University of Utah, Salt Lake City, Utah
Pages: 25 Published: Jan 1962
Only within the last decade has there been evidence of intense interest in the effect of impurities on the properties of nonmetallic materials. Even today, ceramic materials other than germanium and silicon are difficult to obtain with foreign atom concentrations smaller than 100 to 1000 ppm. Yet it is well recognized that impurities strongly affect such properties as bulk and grain boundary diffusion as evidenced by experiments concerning sintering, grain growth, and recrystallization. The property apparently most sensitive to impurities is electrical conductivity; however, this conclusion may have been reached on the basis that this is the most thoroughly studied property of a limited class of ceramic semiconductors, the elements silicon and germanium. Impurities markedly affect thermal conductivity, optical properties, and chemical reactivity. The influence of impurities on the strength of ceramic materials is not thoroughly understood and is the subject of current interest in many laboratories. The above-mentioned properties will not be described with the same thoroughness since adequate reviews exist in certain areas.
Paper ID: STP45071S