Advanced 3Y-TZP bioceramic doped with Al2O3 and MnO2 particles potentially for biomedical applications: study on mechanical and degradation properties

The effectiveness of Al2O3 and MnO2 in enhancing mechanical properties and retarding degradation of 3 mol% yttria stabilized tetragonal zirconia polycrystalline (3Y-TZP) ceramic samples was evaluated by pressureless sintering at temperatures ranging from 1250 C to 1550 C with standard holding time of 2 h. It was observed that the inclusion of Al2O3 and MnO2 into 3Y-TZP was beneficial for the improvement of mechanical properties and ageing resistance. The optimum amounts of dopants were determined to be of 0.6 wt% Al2O3 and 0.4 wt% MnO2. Microstructural investigation revealed that at the same temperature, the tetragonal grain size was not influenced by the increase of dopant levels. With optimum dopants the 3Y-TZP ceramic (density 6.1 g/cm3) samples demonstrated the Vickers hardness of 11.6 GPa, fracture toughness, KIC of 9.8 MPa m1/2, flexural strength of 900 MPa and Young’s modulus of 210 GPa. Furthermore, the efficacy of the dopants (MnO2 and Al2O3) in retarding low-temperature degradation of 3Y-TZP ceramic during exposure in Ringer’s solution at 37 C was also evaluated. Overall, the degradation rate and weight loss of 0.6 wt% Al2O3 and 0.4 wt% MnO2 ceramic samples were 0.66% in 8 weeks as compared to the undoped samples. The 3Y-TZP bioceramic doped with Al2O3 and MnO2 could be a potential candidate material for biomedical applications (e.g. hip implants) due to its improved mechanical properties and superior ageing resistance. © 2017 Published by Elsevier Editora Ltda. on behalf of Brazilian Metallurgical, Materials and Mining Association. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). ∗ Corresponding author. E-mail: mohsen [email protected] (M. Golieskardi). http://dx.doi.org/10.1016/j.jmrt.2017.05.015 2238-7854/© 2017 Published by Elsevier Editora Ltda. on behalf of Brazilian Metallurgical, Materials and Mining Association. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Document downloaded from http://www.elsevier.es, day 27/10/2017. This copy is for personal use. Any transmission of this document by any media or format is strictly prohibited.