Szesz Eduardo M, de Souza Gelson B, de Lima Gabriel G, da Silva Bruno A, Kuromoto Neide K, Lepienski Carlos M
Graduate Program in Engineering and Materials Science (PIPE), Universidade Federal do Paraná UFPR, Curitiba, PR, 81531-990, Brazil.
J Mater Sci Mater Med. 2014 Oct;25(10):2265-75. doi: 10.1007/s10856-014-5238-9. Epub 2014 May 21.
The combination of shot blasting (SB) and micro-arc oxidation (or anodic oxidation--AO) in titanium surfaces was shown to provide enhanced conditions for cell differentiation and osseointegration than those provided by SB or AO alone. This study associated both methods aiming to attain titania layers on Ti with adequate tribo-mechanical features for bone implants. SB was performed using alumina particles, and titania layers were grown by AO using a CaP-based electrolyte. Mechanical properties and scratch resistance were characterized at nanoscale by instrumented indentation and nanoscratch, and correlated with morphological and microstructural changes (XRD, SEM, EDS, AFM, and profilometry). Analytical methods were employed to correct roughness and substrate effects on the indentation results. CaP-containing TiO2 layers were produced on AO and SB + AO. The latter presented small pore size and inhomogeneous layer thickness and Ca/P ratios, caused by the non-uniform surface straining by SB that affects the oxide growth kinetics in the electrochemical process. Elastic modulus of SB + AO layer (37 GPa) were lower than the AO one (45 GPa); both of them were smaller than bulk Ti (130 GPa) and close to bone values. The hardness profiles of AO and SB + AO were similar to the substrate ones. Because of the improved load bearing capacity and unique layer features, the critical load to remove the SB + AO titania coating in scratch tests was three times as much or higher than in AO. Results indicate improved mechanical biocompatibility and tribological strength of anodic titania layers grown on sand blasted Ti surfaces.
与单独使用喷丸处理（SB）或微弧氧化（或阳极氧化 - AO）相比，钛表面的喷丸处理（SB）与微弧氧化相结合被证明能为细胞分化和骨整合提供更有利的条件。本研究将这两种方法结合起来，旨在在钛表面获得具有适合骨植入物的摩擦机械特性的二氧化钛层。使用氧化铝颗粒进行喷丸处理，并使用基于钙磷的电解质通过阳极氧化生长二氧化钛层。通过仪器压痕和纳米划痕在纳米尺度上表征力学性能和耐划痕性，并将其与形态和微观结构变化（XRD、SEM、EDS、AFM和轮廓仪）相关联。采用分析方法校正粗糙度和基材对压痕结果的影响。在阳极氧化和喷丸处理+阳极氧化上制备了含CaP的TiO₂层。后者呈现出小孔径、不均匀的层厚度和Ca/P比，这是由喷丸处理引起的表面应变不均匀导致的，这种不均匀性影响了电化学过程中氧化物的生长动力学。喷丸处理+阳极氧化层的弹性模量（37 GPa）低于阳极氧化层（45 GPa）；两者均小于块状钛（130 GPa）且接近骨值。阳极氧化和喷丸处理+阳极氧化的硬度分布与基材相似。由于承载能力的提高和独特的层特性，在划痕试验中去除喷丸处理+阳极氧化二氧化钛涂层的临界载荷是阳极氧化的三倍或更高。结果表明，在喷砂处理的钛表面生长的阳极二氧化钛层具有更好的机械生物相容性和摩擦学强度。
