Bioactive submicron-pore design of microarc oxidation coating on Ti6Al4V alloy prepared by selective laser melting method

• Published in: Surface & coatings technology Vol. 444; p. 128696
• Main Authors: Wang, Xiao-ming, Zhang, Fu-qin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.08.2022
• Subjects: Bioactive; Microarc oxidation; Selective laser melting; Silicate; Submicron pore; Ti6Al4V; Microarc oxidation; Submicron pore; Silicate; Selective laser melting; Bioactive; Ti6Al4V
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2022.128696

We applied microarc oxidation to create coatings with bioactive submicron pores on the surface of the Ti6Al4V alloy formed via selective laser melting. The effect of adding Na2SiO3, Na2PO4, K2ZrF6 and Na2WO4 to the Na2B4O7 electrolyte on the structure and properties of the MAO coatings was investigated. The “cascade” discharge phenomenon was greatly reduced by adding an extremely small amount of silicate additive into the tetraborate electrolyte. In addition, the MAO coating consisted of submicron pores and a dense, thick, and uniform metallurgical bonding layer. However, microarcs showed a significant “cascade” phenomenon in the other electrolytes, which severely degraded the integrity of the coating. The corrosion resistance of the MAO coating obtained in tetraborate/silicate electrolyte was better than that in the other three electrolytes, and its specific surface area was significantly larger. All the coatings showed better cytocompatibility, protein adsorption capacity, and promoting effect on cell proliferation compared to the Ti6Al4V substrate. However, the RAW264.7 cells adhesion rates on the MAO coatings obtained in the tetraborate/silicate and tetraborate/phosphate electrolytes were significantly better than those in the other electrolytes. The coatings obtained in the tetraborate/silicate electrolyte had the strongest promoting effect on cell proliferation. •Microarc oxidation coatings with submicron pores were created on alloy using additives.•Cascade discharge phenomenon was greatly reduced by adding silicate additive in electrolyte.•It had larger density, corrosion resistance and surface area.•It had strongest promoting effect on cell proliferation.