Firat University, Department of Metallurgical and Materials Engineering, Elazig, 23119, Turkey.
Ataturk University, Department of Metallurgical and Materials Engineering, Erzurum, 25240, Turkey.
J Mater Sci Mater Med. 2021 Apr 1;32(4):40. doi: 10.1007/s10856-021-06514-w.
The hybrid coatings containing the graphene nano-sheet (GNS) and nano-hydroxyapatite (nHA) phases have been successfully synthesized on Ti6Al7Nb alloys by a one-step hydrothermal method. The hydrothermal reaction was carried out for 24 h at 200 °C. The GNS ratio has been altered as 1, 3, 5 and 7 wt.% in the coatings and, the results have compared with non- GNS containing coatings. The effect of the GNS ratio on the microstructure, hardness, and in vitro corrosion responses has been investigated in detail. The characterizations of the coatings were carried out by SEM, EDS, AFM, XRD and, FTIR. The corrosion behavior of the hybrid coatings was compared in Kokubo's solution at 37 °C by using potentiodynamic polarization tests. The results showed that the hydroxyapatite phases were deposed on the graphene layers with nano-size nucleation with its Ca/P stoichiometric ratio. The best hydrophilicity (~52°) property has been obtained in nHA/3GNS coatings. In addition, the corrosion rates of coatings increased in the following order: nHA/3GNS < nHA/1GNS < nHA/7GNS < nHA/5GNS < only nHA.
通过一步水热法成功地在 Ti6Al7Nb 合金上合成了含有石墨烯纳米片（GNS）和纳米羟基磷灰石（nHA）相的混合涂层。水热反应在 200°C 下进行 24 小时。涂层中的 GNS 比例分别为 1、3、5 和 7wt.%，并与不含 GNS 的涂层进行了比较。详细研究了 GNS 比例对微观结构、硬度和体外腐蚀响应的影响。通过 SEM、EDS、AFM、XRD 和 FTIR 对涂层进行了表征。在 37°C 的 Kokubo 溶液中通过动电位极化测试比较了混合涂层的腐蚀行为。结果表明，羟基磷灰石相在具有纳米尺寸成核的石墨烯层上沉积，其 Ca/P 化学计量比。nHA/3GNS 涂层具有最佳的亲水性（~52°）。此外，涂层的腐蚀速率按以下顺序增加：nHA/3GNS< nHA/1GNS< nHA/7GNS< nHA/5GNS< 仅 nHA。
