Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Fabrication of multi-scale periodic line-like structures on different implant materials using a two- beam interference setup equipped with a pico-second laser source
Submission Author:
Bruno Alexandre Pacheco de Castro Henriques , SC
Co-Authors:
Bruno Alexandre Pacheco de Castro Henriques, Bogdan Voisiat, Douglas Fabris, Andres Lasagni
Presenter: Bruno Alexandre Pacheco de Castro Henriques
doi://10.26678/ABCM.COBEM2023.COB2023-2421
Abstract
Surface topography modifications are well-established strategies to improve the biological response of biomaterials and their performance and reliability when used as implants. Studies have shown that surface roughening creates a physical anchorage between the implant and bone and improves its primary and long-term stabilization. Cell proliferation, protein synthesis and cell growth direction can be controlled with well-defined micro- and nanotexture. Conventional techniques to introduce micro- and nanofeatures include acid etching, micromachining, grinding and gritblasting. Although widely used, these techniques present drawbacks that limit their use in advanced engineering applications. Direct Laser Writing (DLW) has emerged as a powerful alternative. In this technique, the feature resolution is limited by the laser beam diameter (usually 5-10 μm). On the other hand, the Direct Laser Interference Patterning (DLIP) technique takes advantage of the physical principle of interference to produce features with spatial resolution similar to the laser wavelength. In this method, the laser is split into two or more beams, which are superposed on the material surface, creating an interference pattern. At the maxima regions, the high energy density causes ablation, while the material is not affected at the minima regions, resulting in periodic structures on the surface. In this work, DLIP method is used for the fabrication of well-defined and flawless multi-scale surface structures in biomedical materials, including zirconia, polyether-ether-ketone (PEEK), AZ91D magnesium alloy, and CobaltChromium-Molybdenum (CoCrMo). A two-beam interference configuration is used, together with an ultrashort pulsed laser, producing high-quality line-like patterns with a period of a few micrometers. Confocal and Scanning Electron Microscopes are utilized to analyze the topography of the manufactured structures, observing significant differences based on the applied process parameters.
Keywords
Microfabrication, Surface structuring, Zirconia, Direct laser interference patterning
