Direct Laser Interference Patterning of zirconia (3Y-TZP)
HENRIQUES B. 1,2,3, VOISIAT B. 2, FABRIS D. 1, GREMILLARD L. 4, BOCCACCINI A. 5, LASAGNI A. 2
1 Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), 88040-900, Florianopolis, SC, Brazil, Florianópolis, Brazil; 2 Institute for Manufacturing Technology, Technische Universität Dresden, George-Baehr-Str.3c, 01069 Dresden, Germany, Dresden, Germany; 3 Center for Micro-Electro Mechanical Systems (CMEMS-UMinho), University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal, Guimarães, Portugal; 4 Univ Lyon, CNRS, INSA Lyon, UCBL, MATEIS, UMR5510, 69100 Villeurbanne, France, Lyon, France; 5 Institute of Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen, Germany, Erlangen, Germany
The unique mechanical, chemical and aesthetic properties of zirconia have turned this ceramic to one of the most studied and used in the biomedical field in general and in prosthetic dentistry in particular. Applications such as dental restorations and dental implants are perhaps the best examples. In both cases, there is the need to proceed to surface modifications of zirconia components either to enhance the adhesion to resin cements or to improve the biological response for osseointegration, respectively. These surface modifications are routinely made using mechanical-based processes such as airborne particle abrasion, producing random roughness profiles and imparting surface damage and phase transformations that can be detrimental to the mechanical performance of the components. The laser-based surface modifications of zirconia have been emerging as an alternative and promising technique as controlled morphologies can be obtained by a contactless process. In this context, the ultra-short pulsed lasers arise as the most appropriate lasers for this end due to the very low or defect less produced surfaces. Additionally, Direct Laser Interference Patterning is a technology that allows creating multiscale periodic structures in a fast and controlled manner. Taking into consideration this background, this study aims at assessing the influence of the DLIP processing parameters on the morphology and microstructure of the zirconia surfaces using a 70 picosecond-pulsed laser source with a wavelength of 532 nm. The surface morphology and resulting microstructure were characterized by White Light Interferometry (WLI), Confocal Microscopy (CM), Scanning Electron Microscopy (SEM) and X-Ray Diffraction. The wettability of the microtextured surface was measured using a Contact Angle Measurement equipment. The subsurface damage was inspected on cross-sectioned surfaces prepared by Focused Ion Beam milling (FIB) on an SEM platform. Line-like hierarchical structures composed by multi-sized interference spatial structures were produced on zirconia surface by tuning the the laser processing parameters.