WEAR-RESISTANCE OF ZIRCONIAS - DIELECTRICAL APPROACH

The wear resistance of stabilized zirconias was investigated on both a ball-on-flat machine and an impact apparatus (Vibratory mill Dangoume au). Those tests allowed us to determine, respectively, the friction r esistance and the impact resistance. If for pure friction it is not ea sy to differentiate the Magnesia Partially Stabilized Zirconias (MgPSZ ) from the Yttria Tetragonal Zirconia Polycrystal (YTZP), after impact tests, we can conclude that the YTZP have a better wear behaviour tha n the MgPSZ, especially in the case of attrition applications. These d ifferences can be explained in terms of test severity and also in term s of energy relaxation. In order to evaluate this last contribution we have studied the dielectrical behavior of our materials, i.e., their ability to store and dissipate polarization energy. (C) 1997 Elsevier Scienbce S.A.