Hou Cong, Nemes-Károly István, Pastrav Leonard, Vrancken Bey, Kocsis Gyorgy, Szebényi Gábor, Czigány Tibor, Denis Kathleen
KU Leuven, Department of Mechanical Engineering, 3001, Leuven, Belgium.
Budapest University of Technology and Economics, Faculty of Mechanical Engineering, Department of Polymer Engineering, 1111, Budapest, Hungary.
J Mech Behav Biomed Mater. 2025 Nov;171:107138. doi: 10.1016/j.jmbbm.2025.107138. Epub 2025 Jul 16.
The failure of artificial joints is often attributed to wear, prompting researchers to explore effective solutions such as material improvement, surface texturing and coating. This study introduces a novel approach of employing 3D printed Voronoi structures to enhance lubrication in polymer-metal sliding wear, with the aim of extending the longevity of artificial joint systems. Specifically, this study investigates the relationship between the geometries and tribological properties of Ti6Al4V Voronoi structures, paired with ultra-high-molecular-weight polyethylene (UHMWPE). The results indicate that the void size in Voronoi structures can be manipulated to match the feature size in the surface texturing approach, suggesting the potential to induce the hydrodynamic effect for friction reduction. The effect of Voronoi structures on reducing friction and wear was examined using pin-on-disc (PoD) tests. In comparison to the control group of solid pins, implementing Voronoi structures in the pins decreases the mean values of static coefficient of friction (COF), dynamic COF, and wear volume by 24.6 %, 29.4 %, and 51.2 %, respectively. Indistinct trends were observed between the COF and the geometric parameters of Voronoi structures. It is hypothesised that interconnected porosity networks within Voronoi structures may preserve wear debris and retain lubricant, potentially elevating hydrodynamic pressure and thereby improving the friction condition. Moreover, comparative analysis of the wear tracks confirms the effective wear reduction achieved by Voronoi structures, with abrasion identified as the primary wear mechanism.
人工关节的失效通常归因于磨损，这促使研究人员探索有效的解决方案，如材料改进、表面纹理化和涂层。本研究引入了一种新颖的方法，即采用3D打印的Voronoi结构来增强聚合物-金属滑动磨损中的润滑，旨在延长人工关节系统的使用寿命。具体而言，本研究调查了Ti6Al4V Voronoi结构与超高分子量聚乙烯（UHMWPE）配对时的几何形状与摩擦学性能之间的关系。结果表明，可以控制Voronoi结构中的孔隙尺寸以匹配表面纹理化方法中的特征尺寸，这表明有可能诱导流体动力效应以减少摩擦。使用销盘（PoD）试验研究了Voronoi结构对减少摩擦和磨损的影响。与实心销的对照组相比，在销中采用Voronoi结构可使静摩擦系数（COF）、动COF和磨损体积的平均值分别降低24.6%、29.4%和51.2%。在COF与Voronoi结构的几何参数之间未观察到明显趋势。据推测，Voronoi结构内相互连接的孔隙网络可能会保留磨损碎屑并留住润滑剂，从而可能提高流体动力压力，进而改善摩擦状况。此外，对磨损轨迹的对比分析证实了Voronoi结构有效减少了磨损，磨损机制主要为磨粒磨损。
