Low-Temperature Aging of Al2O3–[ZrYb]O2 Composites Containing Strontium Hexaaluminate.

The effect of the hydrothermal treatment corresponding to accelerated low-temperature aging and simulating a prolonged exposure to a biological environment on the phase composition and bending strength of Al₂O₃–[ZrYb]O₂ composites containing a variable amount of Al₂O₃ and including strontium hexaaluminate has been investigated. It has been shown that, after the hydrothermal action, the composites retain their bending strength ranging from 700 to 850 MPa, depending on composition. This indicates the preservation of the phase composition in the bulk of the materials. It has been determined that, in the surface layer of the samples, the zirconia monoclinic phase forms in an amount from 11 to 9%, related to the growing alumina content in the composites. Such amounts of the monoclinic zirconia phase formed is well below a limit value of 25% specified by the ISO 13356 2015 standard. The investigated composites can be promising for medical applications. [ABSTRACT FROM AUTHOR]