Purpose

This paper aims to search the optimum content of Ni on the microstructure, phase and electrochemical behavior of high-strength low alloy (HSLA) steel in the 3.5 wt.% NaCl solution.

Design/methodology/approach

The microstructure and corrosion resistance of Ni-containing HSLA steel in the simulated marine environment was studied by optical microscopy, scanning electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical techniques.

Findings

The sample containing 3.55 wt.% of nickel exhibited a finer grain size of 10 μm and a lower i_corr of 2.169 µA cm⁻². The XRD patterns showed that the Fe-Cr-Ni solid solution, FeC and Cr₃C₂ were observed in samples when Ni was added. Besides, the 3.55 wt.% of nickel addition enhanced the charge transfer resistance of the low alloy steel which suggested the sample possessed excellent inhibition of electrochemical reaction and corrosion resistance. The XPS spectrum suggested that nickel was beneficial to improve the corrosion resistance of steel by forming protective oxides, and the ratio of Fe²⁺/Fe³⁺ in protective oxides was increased.

Practical implications

Finding the comprehensive performance of HSLA steel which can be applied to unmanned surface vehicles in marine operations.

Originality/value

This study has a guiding significance for optimizing the composition of HSLA steel in a Cl- containing environment.

中文翻译：

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Ni对含Cl环境下高强低合金钢组织和耐蚀性的影响

目的

本文旨在研究Ni的最佳含量对高强度低合金(HSLA)钢在3.5 wt.% NaCl溶液中的组织、相和电化学行为的影响。

设计/方法/方法

采用光学显微镜、扫描电子显微镜、X射线衍射（XRD）、X射线光电子能谱（XPS）和电化学技术研究了含Ni HSLA钢在模拟海洋环境中的显微组织和耐腐蚀性能。

发现

含有 3.55 wt.% 镍的样品表现出 10 μm 的更细晶粒尺寸和2.169 µA cm ^-2的较低i _corr。XRD图谱表明，当加入Ni时，样品中观察到Fe-Cr-Ni固溶体、FeC和Cr ₃ C ₂。此外，3.55 wt.% 的镍添加量提高了低合金钢的电荷转移电阻，表明样品具有优异的电化学反应抑制和耐腐蚀性。XPS谱表明，镍通过形成保护性氧化物有利于提高钢的耐蚀性，增加了保护性氧化物中Fe ²⁺ /Fe ^{3+ 的}比例。

实际影响

寻找可应用于海上作业无人水面车辆的HSLA钢的综合性能。

原创性/价值

该研究对优化含Cl环境下HSLA钢的成分具有指导意义。