Nickel Aluminium Bronzes (NAB) are copper-based multi-phase alloys used extensively in marine applications. NAB is vulnerable to seawater corrosion, however the interaction between its corrosion mechanisms and real-world factors including biofouling, weld microstructure and residual stress are poorly understood. Seawater corrosion tests were performed on plasma-welded NAB in laboratory and marine environments, demonstrating that the retained β’ phase in the Heat Affected Zone (HAZ) experiences Selective Phase Corrosion (SPC), whereas crevice corrosion associated with SPC of the κ phase occurs at biofouled and stressed areas of parent material. These factors, seldom simulated in physical tests, severely impact NAB’s corrosion resistance.

中文翻译：

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等离子焊接镍铝青铜在海水中的腐蚀机理

镍铝青铜 (NAB) 是广泛用于海洋应用的铜基多相合金。 NAB 很容易受到海水腐蚀，但其腐蚀机制与现实世界因素（包括生物污垢、焊缝微观结构和残余应力）之间的相互作用却知之甚少。在实验室和海洋环境中对等离子焊接 NAB 进行了海水腐蚀测试，表明热影响区 (HAZ) 中的残留 β' 相经历了选择性相腐蚀 (SPC)，而 κ 相的缝隙腐蚀则发生了与 SPC 相关的缝隙腐蚀在母质的生物污染和受压区域。这些在物理测试中很少模拟的因素严重影响了 NAB 的耐腐蚀性。