ABSTRACT

Ni–B and Montmorillonite (MMT)-containing Ni–B deposits were electrolessly plated on AM60B magnesium alloy. The Ni–B coating showed cauliflower-like micromorphology, microcrystalline-amorphous microstructure, and thickness of about 15 μm, which was not influenced by the inclusion of MMT nanoparticles. The surface roughness of the Ni–B coating changed from about 376 to 328 nm after the inclusion of MMT. The boron content of the electroless deposit was mildly increased after MMT inclusion. Thermal shock and porosity examinations revealed suitable adhesion and pore-free structure of the coatings, respectively. Polarization resistance of the Ni–B deposit in 3.5 wt-% sodium chloride was increased about 1.5 times by MMT inclusion. The corrosion current of the substrate was remarkably diminished from 46.89 to 0.12 µA cm⁻² by the Ni–B plating. Also, MMT incorporation causes to further decrement of the corrosion current to about 0.03 µA cm⁻².

摘要

在 AM60B 镁合金上化学镀镍硼和含蒙脱石 (MMT) 的镍硼沉积物。Ni-B 涂层呈现菜花状微观形貌、微晶-非晶微观结构，厚度约为 15 μm，不受 MMT 纳米颗粒的影响。加入 MMT 后，Ni-B 涂层的表面粗糙度从约 376 nm 变为 328 nm。加入 MMT 后，化学镀层的硼含量略有增加。热冲击和孔隙率测试分别显示涂层具有合适的附着力和无孔结构。通过加入 MMT，Ni-B 沉积物在 3.5 wt% 氯化钠中的极化电阻增加了约 1.5 倍。基板的腐蚀电流从 46.89 显着降低到 0.12 µA cm ^-2Ni-B 镀层。此外，MMT 的加入导致腐蚀电流进一步降低至约 0.03 µA cm ^-2。