Plasma Spray Deposition of HA-TiO_2 Composite Coating on Ti-6Al-4V Alloy for Orthopedic Applications

摘要

Titanium and its alloys have been used in medical implants for replacement or repair of organs of the human body in the past few decades, as one of the most common metal biomaterials. Among all the titanium alloys mainly the alpha-beta alloys were widely used in orthopedics and dental applications. This was mainly due to their identical characteristics to human bones such as good fatigue strength, excellent biocompatibility, corrosion resistance, and low specific mass. Although Ti alloys were highly reactive metals which form an oxide (TiO_2) layer on the surface, which is extremely stable and it is preventing the material from corrosion. This layer protects Ti alloys against pitting corrosion, intergranular corrosion, and crevice corrosion, causing Ti alloys to be extremely biocompatible and biomimetic. But, it was observed that with the passage of time, the TiO_2 oxide layer was degraded and unable to prevent the materials from corrosion in the host body. So, the researchers were actively engaged in developing a suitable coating and their technique to improve the stability of implants in the human body. In recent studies, the development/deposition of a composite on the surface of Ti-based implants to improve the mechanical, wear, corrosion, and bioactivity were found the best solution.