Influence of laser texturing on surface features, mechanical properties and low-temperature degradation behavior of 3Y-TZP

This study aims to investigate the influence of different laser surface texturing parameters on Low-Temperature Degradation and mechanical properties of Yttria-tetragonal zirconia polycrystals (3Y-TZP), focused on biomedical applications. The roughness resulted from laser irradiation was characterized by Ra, Rt, Rsk and Rku parameters, as well by SEM analysis. Wettability tests were conducted as a guide to evaluate the ability of the textures to promote osseointegration. Eleven groups of samples were created, such as five according to the laser parameters used, three correspond to the thermal treatments performed and three as different standards. After laser irradiation, all 3Y-TZP samples became black having their whiteness recovered by thermal treatments, which was measured by color analysis. X-Ray photoelectron spectroscopy was used to evaluate chemical changes, presenting the formation of zirconium sub-oxides. These results were corroborated by wettability tests, which exhibited a decrease in surface energy after thermal treatments. Mechanical strength was evaluated by B3B tests, which reveals the potential of laser irradiation combined with thermal treatments for enhancing 3Y-TZP bending resistance and reliability. LTD was accessed by XRD and reveled laser irradiation as a promising approach able to improve the resistance of 3Y-TZP to this phenomenon. © 2019 Elsevier Ltd and Techna Group S.r.l.