Recent advancement in biocompatible materials, hybrid bioactive coating, surface modification and post-processing techniques for the fabrication of biomedical implant: Critical review and future prospects

The demand for various biomedical implants intended for long-term implantation in the human body has increased expeditiously in the recent years. In the past two decades, the field of biomedical applications has experienced substantial and rapid improvements in terms of materials, fabrication processes, and post-processing techniques for implant manufacturing. The major objective of the present study is to assess the interdisciplinary facets of implant manufacturing, analysing their microstructural attributes, tribological capabilities, and mechanical strength, as well as the potential for future enhancements. This work provides a thorough assessment of frequently employed biomaterials, including various metallic substances such as steel, magnesium, cobalt-chrome, and titanium, as well as their corresponding alloys. Additive manufacturing has significant potential for the fabrication of human implants having complex geometry that closely resemble natural biological systems. The potentials of various additive manufacturing processes such as plasma spray, direct metal laser sintering (DMLS), laser directed energy deposition (LDED), physical vapour deposition (PVD) and chemical vapour deposition (CVD) approaches used for the fabrication of several implants are also thoroughly discussed. This study also presents various accelerated testing procedures, including corrosion, corrosion-wear, and fatigue, along with different characterisation approaches.