Parameter optimization and experimental study of the sprocket repairing using laser cladding

In order to achieve the restoration of the sprocket, it is significant to repair or modify the damaged sprocket by using an advanced surface treatment technique, such as the laser cladding process. In this paper, the Taguchi method was applied to conduct the experiment to optimize the process parameters for repairing a sprocket in the laser cladding process. The dilution was chosen to evaluate the quality of the cladding layer and the effect of the process parameters, such as the laser power, scanning speed, and powder feeding rate, with respect to the cladding layer geometry, and the dilution was investigated systematically. Then, using the optimized parameters, the sprocket was remanufactured and its surface profile characteristics, microstructure, and microhardness of the repaired sprocket were analyzed. The results show that the optimal process parameters (1000 W, 2.81 g/min, 1200 mm/min) obtained by the Taguchi method could realize the lower dilution. With the optimal parameters, the repair accuracy of the sprocket could reach 2.973 mm, which offers the machining allowance for machining of the sprocket. A white bright band observed at the interface shows that the metallurgical bonding was realized between the cladding zone and base metal. The microhardness of the cladding zone is higher than that of the heat-affected zone and base metal. Furthermore, the results reveal that the Taguchi method can effectively acquire the optimal combination of process parameters, and the laser cladding process exhibits good feasibility and effectiveness for repairing the machinery components with complex shapes.