A Decade of Progress on MAO-Treated Tantalum Surfaces: Advances and Contributions for Biomedical Applications.

Micro-structured coatings with functional properties have been investigated due to a wide range of applications. It is known that micro-structures can play an important role in surface interactions determining the materials' performance. Amongst the other materials, there has been an increasing interest in tantalum oxide (Ta 2 O 5 ). This attention is mainly due to its variety of properties: biocompatibility and bioactivity; high dielectric constant; good thermal and chemical stability; excellent corrosion and mechanical resistance. Moreover, there is a wide range of applications in which the properties can be fitted. Furthermore, according to the final application, these properties can be enhanced or tailored through surface micro-structures manipulation. Due to this purpose, over the past decade, Ta surface modification by micro-arc oxidation (MAO) has been investigated mostly for biomedical applications. Therefore, this review focuses on Ta surface functionalization using the MAO technique. A clear understanding of the micro-discharge phenomena and the formation mechanism of a Ta 2 O 5 anodic coating by MAO is supplied. The Ta 2 O 5 coating morphology, topography, chemistry, and structure are explored, establishing their correlation with the MAO parameters. Additionally, an understanding of Ta 2 O 5 's biological, mechanical, and electrochemical properties is provided and reviewed.