CrN, TiN and AlTiN coatings were applied by the Physical Vapour Deposition (PVD) method on AISI 4140 and plasma nitrided (PN) AISI 4140 steel. The study aimed to investigate the effect of plasma nitriding before PVD on the corrosion and tribocorrosion behaviour of AISI 4140 steel in seawater. The electrochemical corrosion behaviour of the samples was evaluated in natural seawater by the potentiodynamic polarisation method. Tribocorrosion tests were performed against alumina in natural seawater under 5 N load and open circuit potential (OCP) using a ball-on-disk tribometer coupled with an electrochemical cell. As a result of the study, plasma nitriding applied before the coating significantly improved corrosion and tribocorrosion resistance of PVD CrN, TiN and AlTiN coatings. Besides, it was concluded that duplex treated low alloy AISI 4140 steel could be a candidate instead of stainless steel in tribocorrosion conditions for the marine environment.

中文翻译：

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等离子渗氮预处理对 PVD ​​CrN、TiN 和 AlTiN 涂层 AISI 4140 钢在海水中腐蚀和摩擦腐蚀行为的影响

CrN、TiN 和 AlTiN 涂层通过物理气相沉积 (PVD) 方法应用于 AISI 4140 和等离子氮化 (PN) AISI 4140 钢。本研究旨在研究 PVD ​​前等离子渗氮对 AISI 4140 钢在海水中的腐蚀和摩擦腐蚀行为的影响。采用动电位极化法评价样品在天然海水中的电化学腐蚀行为。在 5 N 负载和开路电位 (OCP) 下，使用与电化学电池耦合的球盘摩擦磨损计对天然海水中的氧化铝进行摩擦腐蚀测试。作为研究的结果，在涂层之前应用等离子渗氮显着提高了 PVD ​​CrN、TiN 和 AlTiN 涂层的耐腐蚀性和耐摩擦腐蚀性能。除了，