| LIAO Wanda,LI Rupeng,LI Zhuoyi,BAI Changning,ZHANG Xingkai.Anti-corrosion and Tribological Performance of Nickel-phosphorus Coating by Galvanic Replacement-free Electroless Deposited Gold Layer[J],54(4):122-129 |
| Anti-corrosion and Tribological Performance of Nickel-phosphorus Coating by Galvanic Replacement-free Electroless Deposited Gold Layer |
| Received:March 20, 2024 Revised:November 10, 2024 |
| View Full Text View/Add Comment Download reader |
| DOI：10.16490/j.cnki.issn.1001-3660.2025.04.009 |
| KeyWord:liquid phase deposition nickel-phosphorus coating gold layer corrosion friction |
| Author | Institution |
| LIAO Wanda |
Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou , China |
| LI Rupeng |
Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou , China |
| LI Zhuoyi |
Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou , China |
| BAI Changning |
Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou , China |
| ZHANG Xingkai |
Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou , China |
|
| Hits: |
| Download times: |
| Abstract: |
| The gold layer possesses excellent corrosion resistance and lubricating properties. However, when a gold layer on a metal substrate, galvanic replacement reactions often lead to interfacial and intrinsic defects, compromising the corrosion resistance and other properties of the coating. By inhibiting the replacement reaction between the gold ions and the nickel-phosphorus (Ni-P) coating, the formation of defects such as pores in the gold layer can be avoided, thereby enhancing the corrosion and wear resistance of the Ni-P coating. Using aluminum as the sacrificial anode in contact with the Ni-P coating can avoid the corrosion of the Ni-P coating substrate by alkaline gold plating solution. Meanwhile, the strong chelating ability of sodium sulfite in alkaline gold plating solution can also limit the replacement reaction between the gold ions and the Ni-P coating. At the same time, the aluminum can form primary battery with Ni-P coating, providing electrons for the reduction and deposition of gold ions on the surface of Ni-P coating in the solution. A dense gold layer with a thickness of 250 nanometers was prepared on the surface of Ni-P coating by the contact plating method. The surface morphology, composition, and structure of the gold layer on the Ni-P coating were analyzed with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The μ Autolab III electrochemical workstation and reciprocating friction testing machine were used to study the corrosion resistance and tribological performance of the Ni-P coating and the Ni-P/gold coating. After deposition of the gold layer, the typical nodular surface morphology of the Ni-P coating significantly changed. The gold layer was mainly composed of densely packed particles with irregular shapes and varying sizes (between 100 and 200 nanometers), and the Ni-P coating below the gold layer was not corroded. Among them, the Ni-P coating exhibited amorphous structure, while the gold layer had a fcc-Au crystal structure. The Ni-P/gold coating exhibited excellent corrosion resistance and tribological performance, which could be attributed to the dense structure and chemical stability of the gold layer, as well as high ductility and low hardness. Compared to the corrosion potential (Ecorr) of −0.486 V and corrosion current density (Jcorr) of 666.84 nA/cm2 for the aluminum substrate, the Ecorr for the Ni-P coating increased to −0.152 V, while Jcorr decreased to 426.71 nA/cm2. The performance of the gold layer was particularly notable, with its Ecorr increasing to 0.125 V and Jcorr dropping to 225.32 nA/cm2. The gold layer exhibited a significant advantage in terms of tribological performance, reducing the friction coefficient of the Ni-P coating from 0.64 to 0.17 and also improving the wear resistance. The presented wear track images of the Ni-P coating with and without the gold layer indicated that the wear of gold layer was relatively light with a wear track width of only 140 μm. In contrast, the wear of the Ni-P coating was more severe with a wear track width of 375 μm. A galvanic replacement-free contact plating method is proposed for depositing the gold layer on the surface of Ni-P coating. Electrochemical and tribological tests show that the prepared gold layer can significantly improve the corrosion resistance and tribological performance of the Ni-P coating. |
| Close |
|
|
|