Abstract Laser hot-wire cladding (LHWC) is a hybrid deposition process where the wire is preheated by resistant heat during the deposition process. This process can dramatically increase the deposition efficiency and the material utilization rate. In this study, a cobalt-based metal cored wire was deposited by using laser hot-wire cladding. The CMOS camera assisted by a green laser illumination was used to monitor the stability of the deposition process and to investigate the molten pool width and length. The effects of processing parameters such as wire feed rate and scanning speed on the clad geometrical characteristics (height, wetting angle, and dilution rate) were studied in detail. The variation of the secondary dendrite arm spacing (SDAS) and microhardness with different processing parameters was discussed. The microstructure and corrosion resistance of the deposited alloy were finally analyzed. It was found that the resistant heat applied on the wire was a dominate factor influencing the stability of the deposition process. The clad height could be predicted by measuring the molten pool width. The molten pool length could be used as an indicator to reflect the cooling rate of the process. The clad height, wetting angle, and dilution rate were all sensitive to the wire feed rate and the scanning speed. The microhardness was mainly determined by the dilution rate. A high dilution rate decreased the clad hardness. The microstructure of the deposited alloy had a typical hypo-eutectic structure. An improved corrosion resistance of the deposited coating was obtained when compared to the substrate.

中文翻译：

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Co-Cr-W金属包芯线的激光热熔覆

摘要 激光热线熔覆 (LHWC) 是一种混合沉积工艺，在沉积过程中，金属丝通过电阻热进行预热。该工艺可以显着提高沉积效率和材料利用率。在这项研究中，使用激光热熔丝包覆沉积了钴基金属包芯线。由绿色激光照明辅助的 CMOS 相机用于监测沉积过程的稳定性并研究熔池的宽度和长度。详细研究了送丝速度和扫描速度等加工参数对包层几何特性（高度、润湿角和稀释率）的影响。讨论了不同加工参数下二次枝晶臂间距（SDAS）和显微硬度的变化。最后分析了熔敷合金的显微组织和耐腐蚀性能。发现施加在导线上的耐热热是影响沉积过程稳定性的主要因素。可以通过测量熔池宽度来预测包层高度。熔池长度可作为反映工艺冷却速度的指标。包层高度、润湿角和稀释率都对送丝速度和扫描速度敏感。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。发现施加在导线上的耐热热是影响沉积过程稳定性的主要因素。可以通过测量熔池宽度来预测包层高度。熔池长度可作为反映工艺冷却速度的指标。包层高度、润湿角和稀释率都对送丝速度和扫描速度敏感。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。发现施加在导线上的耐热性是影响沉积过程稳定性的主要因素。可以通过测量熔池宽度来预测包层高度。熔池长度可作为反映工艺冷却速度的指标。包层高度、润湿角和稀释率都对送丝速度和扫描速度敏感。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。可以通过测量熔池宽度来预测包层高度。熔池长度可作为反映工艺冷却速度的指标。包层高度、润湿角和稀释率都对送丝速度和扫描速度敏感。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。可以通过测量熔池宽度来预测包层高度。熔池长度可作为反映工艺冷却速度的指标。包层高度、润湿角和稀释率都对送丝速度和扫描速度敏感。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。显微硬度主要由稀释率决定。高稀释率降低了包层硬度。沉积合金的显微组织具有典型的亚共晶结构。与基材相比，沉积涂层的耐腐蚀性得到改善。