Structures with Phase Contacts

The formation of disperse structures with phase contacts takes place under a great variety of physical-chemical conditions, for instance during sintering and pressing of powders. Disperse systems with phase contacts that form in the course of condensation of a new phase from metastable solutions or melts, are commonly referred to as condensation. If the particles that form... 

Surface Phenomena in the Structures with Phase Contacts and in Continuous Solid Bodies... 

One can thus conclude that any given structure may contain both coagulation (residual) and phase (newly formed) contacts. Depending on the prevailing type of contacts, the structures can be subdivided into two large classes coagulation structures and structures with phase contacts. 

Disperse structures with phase contacts can form in a variety of physical-chemical processes, such as in the sintering of ceramic powders and in the course of pressing powders into pellets. Disperse structures with phase contacts that are formed in the process of generating a new phase in metastable solutions or melts are referred to as condensation structures. If the particles forming structures are crystalline, then the structures are referred to as condensation-crystallization structures. These structures can be viewed as opposite to the condensation structures composed of amorphous particles. 

Structures with phase contacts represent the foundation for the formation of most materials. The formation of phase contacts can be the principal stage in the formation of continuous bodies or the final stage in the formation of porous bodies. 

One can say that in some cases the formation of structures with phase contacts is favorable, as it carries with it an increase in strength, while in other cases it should be either minimized or prevented. 

The entire spectrum of natural and technological processes involving the formation of structures with phase contacts is very broad. Some principal publications on this matter are listed in References 11-24. In addition to essential studies conducted by the author [1-8], other significant publications relevant to the subject matter discussed in this chapter are listed in References 25-37. 

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