Li Tianqing, Bi Zhiwei, Lei Yucheng
School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China.
Materials (Basel). 2024 Sep 27;17(19):4758. doi: 10.3390/ma17194758.
Improving the wear resistance and corrosion resistance of 60Si2Mn steel is an important issue in agricultural machinery. A Rockit 606 coating layer may exhibit excellent performance in wear resistance and corrosion resistance. However, there are very a few public reports and articles involving the topic of a Rockit 606 laser cladding layer on a steel 60Si2Mn surface. It is of great importance to research Rockit 606 laser cladding layers. This work focuses on studying the microstructure and properties of Rockit 606 coating layers with different scanning speeds by disk laser cladding. Firstly, the laser cladding platform was designed and set up. Secondly, the laser cladding parameters were designed, and then the laser cladding experiment was conducted, and the Rockit 606 coating layers were obtained. And finally, the microstructure, phase distribution, corrosion resistance, surface hardness, and wear resistance of the coating layers were measured and analyzed. A scanning electron microscope (SEM), X-ray diffractometer (XRD), electrochemical workstation, and microhardness tester were used in this work. It was found that the microstructure Rockit 606 alloy coating consists of γ-Fe, VC, and CrC. The microhardness of the Rockit 606 alloy coatings decreased with an increase in the scanning speed. When the scanning speed was 4 mm/s, the highest microhardness value reached 867.2 HV, which is about three times of that of the substrate. The average coefficients of friction (COFs) of the coatings decreased with an increase in the scanning speed, which led to the corresponding decrease of the wear rate. When the scanning speed was 4 mm/s, the wear behavior of the coating was mainly oxidative wear and a small amount of adhesive wear. The self-corrosion current density of the coatings prepared by laser cladding in a 3.5 wt.% NaCl solution is one order of magnitude lower than that of the substrate, indicating that the coatings have better corrosion resistance properties.
提高60Si2Mn钢的耐磨性和耐腐蚀性是农业机械领域的一个重要问题。Rockit 606涂层可能在耐磨性和耐腐蚀性方面表现出优异的性能。然而，关于在60Si2Mn钢表面进行Rockit 606激光熔覆层这一主题的公开报告和文章非常少。研究Rockit 606激光熔覆层具有重要意义。这项工作聚焦于通过圆盘激光熔覆研究不同扫描速度下Rockit 606涂层的微观结构和性能。首先，设计并搭建了激光熔覆平台。其次，设计了激光熔覆参数，然后进行了激光熔覆实验，获得了Rockit 606涂层。最后，对涂层的微观结构、相分布、耐腐蚀性、表面硬度和耐磨性进行了测量和分析。本工作使用了扫描电子显微镜（SEM）、X射线衍射仪（XRD）、电化学工作站和显微硬度计。研究发现，Rockit 606合金涂层的微观结构由γ-Fe、VC和CrC组成。Rockit 606合金涂层的显微硬度随扫描速度的增加而降低。当扫描速度为4 mm/s时，最高显微硬度值达到867.2 HV，约为基体的三倍。涂层的平均摩擦系数（COF）随扫描速度的增加而降低，这导致磨损率相应降低。当扫描速度为4 mm/s时，涂层的磨损行为主要为氧化磨损和少量粘着磨损。在3.5 wt.% NaCl溶液中通过激光熔覆制备的涂层的自腐蚀电流密度比基体低一个数量级，表明涂层具有更好的耐腐蚀性能。
