TABLE OF CONTENTS The application of ceramics has infiltrated almost all fields in the last 20 years, because of their advantages over metals due to their strong ionic or covalent bonding. But it is just this bonding nature of ceramics that directly results in their inherent brittleness and difficulty in machining. In other words, ceramics show hardly any macroscopic plasticity at room temperature or at low temperatures like metals. Hence, superplasticity at room temperature is a research objective for structural ceramics. In recent years, many researches have been carried out to investigate nanophase ceramic composites.
Depending on the matrix grain size, nanophase ceramic composites can be classified in two fundamental groups. One is composed of micrometer-sized matrices dispersed with a nanometer second phase, which has attracted a lot of interest in the last 15 years. In this group, the second phase plays a crucial role that affects the microstructure and the properties. Niihara [ [1]] has divided it into three types intragranular, intergranular and intra-/intergranular trying to relate the distribution of the second nanophase in the matrix. Niihara and co-workers have reported dramatic improvements in toughness, strength at room temperature and high temperatures, creep strength and thermal shock resistance by incorporating nanocrystalline dispersion in a...
