Sizes and Spacings of Structure Constituents

In observing microstructures, it is frequently found that there are two or more levels of structure  

A structure associated with the distribution of relatively large pores, grog (prefired clay) particles, or other grains in a matrix phase 

A structure of phase distribution within the large grains and within the bond phase 

A structure that shows the distribution of dislocations and the separation between various structure constituents 

It is often necessary to use different techniques for a study of each of these characteristics. For example, we may use a thin or polished section to study the large-scale structure coming under level 1. We will have to use scanning electron microscopy to study a fine clay matrix of level 2 structures. Determining which level of structure is the most important depends on the particular ceramic and the particular property of interest. 

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