Structure and mechanical properties of the CaO–ZrO$_{2}$–Al$_{2}$O$_{3}$ ceramic composites at low corundum concentrations

We have studied the effect of the ratio between concentrations of zirconium dioxide (stabilized by CaO) and corundum on phase composition and mechanical properties of nanostructured CaO–ZrO$_{2}$–Al$_{2}$O$_{3}$ ceramic composites. The CaO–ZrO$_{2}$–Al$_{2}$O$_{3}$ composites sintered at temperatures typical of ZrO$_2$ are found to be characterized by the optimal microhardness/fracture toughness ratio at corundum content C$_{\mathrm{Al}_{2}\mathrm{O}_{3}}$ = 5%. These composites have a high flexural strength; their porosity, coefficient of friction, and wear are typical of those for CaO–ZrO$_2$ ceramics.