**4. Conclusions**

Microwave sintering has a very noticeable effect on the properties of ATZ material and therefore on their susceptibility to degradation at low temperatures. The ATZ composite has been obtained with densities close to theoretical densities by

*Design and Development of Zirconia-Alumina Bioceramics Obtained at Low Temperature… DOI: http://dx.doi.org/10.5772/intechopen.102903*

microwave heating, considerably reducing sintering times compared with the conventional sintering method. Microwave heating is accompanied by modification of the densification mechanisms, giving the ATZ material excellent mechanical properties.

In sample MW1300\_10, the amount of the monoclinic phase is lower than for CS1500\_120 after the same hours of exposure to LTD conditions. Therefore, the non-conventional fast technique of microwave sintering is a great alternative since it requires lower temperatures and times for densification, giving materials more resistant to low-temperature degradation.

The addition of alumina to the composition makes the phase change more difficult, the ATZ composite being more resistant to degradation than monolithic zirconia material.

In summary, there are many variables that can influence the resistance to LTD, including the composition of the material, quantity and distribution of the stabilizer or the sintering mechanisms among others. In this work, the results obtained indicate that both the addition of alumina in the composition and the use of microwaves as a sintering method favor the resistance to aging, occurring at a lower speed. There is no earlier publication on the effect of microwave sintering on the behavior of the LTD on ATZ materials, so this work is an approximation to understand this phenomenon.
