Stabilization of the Zr O2.Mg O and sintering of powder doped with Ti O2, Cu O, and Zn O

The stabilization and the sintering of the Zr O2 system have been studied together with Mg O the addition of Ti O2, Cu O and Zn O. It was observed that the presence of the Ti O2 does not stabilize the zirconia-magnesia due to the formation of the Zirconium Titanate. On the other hand, the presence of Cu O and Zn O favored specially the stabilization of the tetragonal phase. the addition of 0,1 mol% of Ti O2 increased the volume of unit cell from 141,8 to 142,9 A3, being that addition of Cu O and Zn O increased the volumes of the unit cells from 132,0 and 130,8 to 132,8 A3, respectively. This was attributed to the different effects of the crystalline field that favored the sp2 d5 orbital in the Zr O2. Mg O. Zn O system and the Jahn Teller effect in the Zr O2.Mg O.Cu O system. These orbitals promoted a raise in the stabilization of the zirconia-magnesia system. The studies of the sintering by dilatometry of the Zr O2.Mg O system with the Ti O2 and Zn O showed that the dominant mechanism was that of the lattice diffusion type. Meanwhile, in the Zr O2.Mg O.Cu O system the mechanism observed was that of the viscous flow type. The activation energies were calculated by both the Arrhenius and the Banister equations for all the conditions of this study. The values of the energies of the Zr O2. Mg O system with the Ti O2, Cu O and Zn O were: 462, 438 and 301,4 K J/mol by Arrhenius and 371, 541 and 341, 5 kJ/mol by Banister, respectively. (author). 64 refs., 40 figs., 9 tabs