Umar Farooq Muhammad, Pervez Mughal Mohammad, Ahmed Naveed, Ahmad Mufti Nadeem, Al-Ahmari Abdulrahman M, He Yong
Department of Industrial and Manufacturing Engineering, University of Engineering and Technology, Lahore 39161, Pakistan.
Industrial Engineering Department, College of Engineering and Architecture, Al-Yamamah University, Riyadh 11512, Saudi Arabia.
Materials (Basel). 2020 Mar 27;13(7):1549. doi: 10.3390/ma13071549.
Surface modification is given vital importance in the biomedical industry to cope with surface tissue growth problems. Conventionally, basic surface treatment methods are used which include physical and chemical deposition. The major drawbacks associated with these methods are excessive cost and poor adhesion of coating with implant material. To generate a bioactive surface on an implant, electric discharge machining (EDM) is a promising and emerging technology which simultaneously serves as machining and surface modification technique. Besides the surface topology, implant material plays a very important role in surgical applications. From various implant materials, titanium (Ti6Al4V ELI) alloy is the best choice for long-term hard body tissue replacement due to its superior engineering, excellent biocompatibility and antibacterial properties. In this research, EDM's surface characteristics are explored using Si powder mixed in dielectric on Ti6Al4V ELI. The effect of powder concentration (5 g/L, 10 g/L and 20 g/L) along with pulse current and pulse on time is investigated on micro and nanoscale surface topography. Optimized process parameters having a 5 g/L powder concentration result in 2.76 μm surface roughness and 13.80 μm recast layer thickness. Furthermore, a nano-structured (50-200 nm) biocompatible surface is fabricated on the surface for better cell attachment and growth. A highly favourable carbon enriched surface is confirmed through EDS which increases adhesion and proliferation of human osteoblasts.
在生物医学行业中，表面改性对于解决表面组织生长问题至关重要。传统上，使用包括物理和化学沉积在内的基本表面处理方法。这些方法的主要缺点是成本过高以及涂层与植入材料的附着力差。为了在植入物上生成生物活性表面，电火花加工（EDM）是一种有前途的新兴技术，它同时作为加工和表面改性技术。除了表面拓扑结构外，植入材料在外科应用中也起着非常重要的作用。在各种植入材料中，钛（Ti6Al4V ELI）合金因其卓越的工程性能、出色的生物相容性和抗菌性能，是长期硬组织替代的最佳选择。在本研究中，使用在Ti6Al4V ELI的电介质中混合的硅粉来探索电火花加工的表面特性。研究了粉末浓度（5 g/L、10 g/L和20 g/L）以及脉冲电流和脉冲导通时间对微观和纳米尺度表面形貌的影响。粉末浓度为5 g/L的优化工艺参数导致表面粗糙度为2.76μm，重铸层厚度为13.80μm。此外，在表面制备了纳米结构（50 - 200 nm）的生物相容性表面，以实现更好的细胞附着和生长。通过能谱分析（EDS）证实了一个高度有利的富碳表面，该表面增加了人成骨细胞的附着力和增殖。
