Wang Yiyong, Liang Zhipeng, Zhang Junwei, Ning Zhe, Jin Hui
College of Material and Metallurgy, University of Science and Technology Liaoning, Anshan 114051, China.
Materials (Basel). 2016 Jul 28;9(8):634. doi: 10.3390/ma9080634.
Ni-Co duplex coatings were cladded onto Cu to improve the antiwear properties of Cu products. Prior to laser cladding, n-Al₂O₃/Ni layers were introduced as interlayers between laser cladding coatings and Cu substrates to improve the laser absorptivity of these substrates and ensure defect-free laser cladding coatings. The structure and morphology of the coatings were characterized by scanning electron microscopy and optical microscopy, and the phases of the coatings were analyzed by X-ray diffraction. Their hardness was measured using a microhardness tester. Experimental results showed that defect-free composite coatings were obtained and that the coatings were metallurgically bonded to the substrates. The surface of the Ni-Co duplex coatings comprised a Co-based solid solution, Cr₇C₃, (Fe,Ni)C₆, and other strengthening phases. The microhardness and wear resistance of the duplex coatings were significantly improved compared with the Cu substrates. The average microhardness of the cladded coatings was 845.6 HV, which was approximately 8.2 times greater than that of the Cu substrates (102.6 HV). The volume loss of the Cu substrates was approximately 7.5 times greater than that of the Ni-Co duplex coatings after 60 min of sliding wear testing. The high hardness of and lack of defects in the Ni-Co duplex coatings reduced the plastic deformation and adhesive wear of the Cu substrates, resulting in improved wear properties.
将镍钴双层涂层熔覆在铜上，以提高铜制品的抗磨损性能。在激光熔覆之前，引入n-Al₂O₃/Ni层作为激光熔覆涂层与铜基体之间的中间层，以提高这些基体的激光吸收率，并确保获得无缺陷的激光熔覆涂层。通过扫描电子显微镜和光学显微镜对涂层的结构和形貌进行表征，并用X射线衍射分析涂层的相组成。使用显微硬度计测量其硬度。实验结果表明，获得了无缺陷的复合涂层，且涂层与基体实现了冶金结合。镍钴双层涂层的表面由钴基固溶体、Cr₇C₃、(Fe,Ni)C₆和其他强化相组成。与铜基体相比，双层涂层的显微硬度和耐磨性显著提高。熔覆涂层的平均显微硬度为845.6 HV，约为铜基体（102.6 HV）的8.2倍。在进行60分钟的滑动磨损试验后，铜基体的体积损失约为镍钴双层涂层的7.5倍。镍钴双层涂层的高硬度和无缺陷减少了铜基体的塑性变形和粘着磨损，从而改善了磨损性能。
