Electroless deposition and characterization of a double-layered Ni-B/Ni-P coating on AZ91D Mg alloy from eco-friendly fluoride-free baths
Electroless deposition and characterization of a double-layered Ni-B/Ni-P coating on AZ91D Mg alloy from eco-friendly fluoride-free baths
复制标题
采用环保无氟镀液在 AZ91D 镁合金上进行双层 Ni-B/Ni-P 涂层的化学沉积和表征
DOI：
10.1016/j.surfcoat.2018.02.105
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发表时间：
2018-05-25
影响因子：
5.4
通讯作者：
Yu, Gang
中科院分区：
文献类型：
--
作者：
Zhang, Jun;Xie, Zhi-Hui;Yu, Gang
化学沉积镍因其良好的性能，尤其是缓蚀性能，在镁合金表面改性方面引起了人们的广泛兴趣。采用环保型无氟化学镀液，以Ni-B为底层，Ni-P为外层，在AZ 91 D镁合金表面成功制备了Ni-B/Ni-P双层化学镀层。采用扫描电子显微镜（SEM）、能谱仪（EDS）、X射线光电子能谱仪（XPS）和X射线衍射仪（XRD）分别对涂层的形貌、成分和相结构进行了表征。采用线性扫描伏安法、计时电流法和电化学阻抗谱（EIS）等电化学技术对Ni-B/Ni-P复合镀层的沉积过程进行了分析，证实了Ni-B/Ni-P复合镀层的缓蚀性能。此外，与镁合金和单一Ni-P镀层相比，新设计的复合镀层的显微硬度也有显著提高。
Electroless Ni deposition has attracted much interest in surface modification of Mg alloy owing to its good performance, especially in corrosion inhibition. In this work, an electroless double-layered Ni-B/Ni-P coating on AZ91D Mg alloy was fabricated successfully by plating of a Ni-B layer as primer and a Ni-P layer as outer layer from eco-friendly fluoride-free plating baths. The morphology, composition, and phase structure of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS), and X-ray diffractometer (XRD), respectively. Several different electro-chemical techniques such as linear sweep voltammetry, chronoamperometry, and electrochemical impedance spectroscopies (EIS) were used to analyze the deposition process and demonstrate the enhancement of corrosion inhibition of the Ni-B/Ni-P duplex coating. In addition, compared with Mg alloy and a single Ni-P coating, the new-designed duplex coating also exhibits a remarkable enhancement in micro-hardness.