Chemical Manufacturing Processes

Abstract

The development of the microcomputer has had an enormous impact on both society as a whole and on industry in particular. Its influence has been felt in the field of materials technology, in that the range of material functions has been considerably increased and as a direct result the use of these materials has also inevitably increased. For this reason the reliability of materials has become a matter of some considerable concern. The principal characteristics of a material depend not so much on its physical as on its chemical properties. We have so far, however, concentrated almost exclusively on the physical properties of materials insofar as they have a direct connection with production methods and have made little mention of their chemical properties or of the relative advantages and disadvantages of the various different production methods from the point of view of chemical composition. It has, however, become abundantly clear that our objective of high material reliability depends in large measure on chemical properties such as the chemical composition of particles, the compositional changes which take place either within particles or at particle level and the secondary phase physical forms of particles. In this chapter we have focused our attention on those methods of producing fine particles which make use of chemical reactions at the various stages of the production process and also on the chemical composition and structure of particles generated by these various methods.