Properties of CaO-ZrO2 Based Composites

Composites of ZrO2-CA2 were sintered by the conventional technique at 1400° C from mixtures of m-ZrO2 with different amounts of high alumina cement containing CaO. The effect of the change in the composition on some properties such as: density, porosity, size and volume of pores, hardness and elasticity modulus of the composites was analyzed. Young's modulus was determined experimentally by the technique of excitation by impulse and hardness was evaluated by the Vickers method. The main phases identified by XRD were m-ZrO2, c-ZrO2 (CaO0.15 Zr0.85O1.85) and CA2 (CaAl4O7). An increase in the content of phase c-ZrO2 (CaO stabilized zirconia) was observed with increasing aluminous cement content. The apparent density decreased whereas porosity and pore volume increased by increasing the content of CaO. Hardness and elasticity modulus showed a clear dependence on composition and porosity of the composites.