Mechanical properties research of corundum ceramics at change of porosity and the crystallites sizes

It has been studied strength of alumina ceramic based on powders produced by thermal decomposition of hydroxide aluminum and the plasma-spray pyrolysis methods. It was shown that at 60wt.% of plasmachemical powder Al2O3 in mixture one can observed a sharp changes of strength which depends on the porosity. The approximation of dependence of strength vs. average grain size to porousless state shows a possibility of obtaining ceramics with almost theoretical strength. It was found a correlation between microstresses and macrostress in sintered ceramics.