Purpose

The commercial stainless steels have been used extensively in the biomedicine application and their electrochemical behaviour in the simulated body fluid (SBF) are not uncovered obviously. In this research, the corrosion resistance of the commercial stainless steel of Fe–17Cr–xNi alloys (x = 4, 8, 10 and 14) has been studied. This study aims to evaluate the rate of corrosion and corrosion resistance of some Fe–Cr–Ni alloys in SBF at 37°C.

Design/methodology/approach

In this research, the corrosion resistance of the commercial stainless steel of Fe–17Cr–xNi alloys has been studied using open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization in the SBF at 37°C and pH 7.4 for a week. Also, the surface morphology of the four alloys was investigated using scanning electron microscopy, elemental composition was obtained via energy dispersive spectroscopy and the crystal lattice structure of Fe–17Cr–xNi alloys was obtained using X-ray diffraction technique. The chemical structure of the protective oxide film has been examined by X-ray photoelectron spectroscopy (XPS) and metals ions released into the solution have been detected after different immersion time using atomic absorption spectroscopy.

Findings

The results revealed that the increase of the Ni content leads to the formation of the stable protective film on the alloys such as the Fe–17Cr–10Ni and Fe–17Cr–14Ni alloys which possess solid solution properties. The Fe–17Cr–14Ni alloy displayed highest resistance of corrosion, notable resistance for localized corrosion and the low corrosion rate in SBF because of the formation of a homogenously protective oxide film on the surface. The XPS analysis showed that the elemental Fe, Cr and Ni react with the electrolyte medium and the passive film is mainly composed of Cr₂O₃ with some amounts of Fe(II) hydroxide at pH 7.4.

Originality/value

This work includes important investigation to use commercial stainless steel alloys for biomedical application.

中文翻译：

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一些商业不锈钢合金在模拟体液电解质中的电化学行为

目的

商业不锈钢已广泛用于生物医学应用，其在模拟体液 (SBF) 中的电化学行为并未明显发现。在这项研究中，研究了 Fe-17Cr-xNi 合金（x = 4、8、10 和 14）的商用不锈钢的耐腐蚀性。本研究旨在评估某些 Fe-Cr-Ni 合金在 37°C 下 SBF 中的腐蚀速率和耐蚀性。

设计/方法/方法

在这项研究中，在 37°C 和 pH 7.4 下，使用开路电位、电化学阻抗谱和动电位极化在 SBF 中研究了 Fe-17Cr-xNi 合金商用不锈钢的耐腐蚀性能。此外，使用扫描电子显微镜研究了四种合金的表面形貌，通过能量色散光谱获得元素组成，使用 X 射线衍射技术获得 Fe-17Cr-xNi 合金的晶格结构。保护性氧化膜的化学结构已通过 X 射线光电子能谱 (XPS) 进行了检查，并使用原子吸收光谱法检测了不同浸泡时间后释放到溶液中的金属离子。

发现

结果表明，Ni含量的增加导致在具有固溶性质的Fe-17Cr-10Ni和Fe-17Cr-14Ni合金等合金上形成稳定的保护膜。Fe-17Cr-14Ni 合金在 SBF 中表现出最高的耐腐蚀性、显着的耐局部腐蚀和低腐蚀速率，因为在表面上形成了均匀的保护性氧化膜。XPS 分析表明，元素 Fe、Cr 和 Ni 与电解质介质发生反应，钝化膜主要由 Cr ₂ O ₃和一定量的 Fe(II) 氢氧化物组成，pH 值为 7.4。

原创性/价值

这项工作包括将商业不锈钢合金用于生物医学应用的重要调查。