Average Grain Size in Polycrystalline Ceramics

A model is proposed which realistically characterizes the grain structure of polycrystalline ceramics. The average grain size of a log-normal distribution of grain sizes with tetrakaidecahedral (truncated octahedral) shape is related to the average intercept size by a proportionality constant. This result can be used to determine the average grain size of a sintered powder compact composed of nontextured grains which shows no discontinuous grain growth.