ABSTRACT
Investigations on cyclic fatigue behaviour of Mg-PSZ reported in literature have been exclusively on subeutectoid-aged materials. In this paper we present the results of a study of the crack resistance and fatigue behaviour of Mg-PSZ in the absence of the δ-phase (Mg2Zr5O12), by using specimens rapidly cooled from the sintering temperature and aged at the eutectoid temperature, 1400 °C, for various times. Inert strength testing of specimens with controlled indentation flaws gave a measure of the strength as well as flaw tolerance of the materials. SEM and neutron diffraction were used to characterize the microstructure and phase assemblage. Under-, peak-and over-aged conditions were identified and the latter two conditions selected for R-curve and static and cyclic fatigue testing. The results and their relationship with the microstructure are discussed and compared with those previously obtained for subeutectoid-aged materials.
