Research on Heat and Mass Transfer in Wide-band Laser Cladding Molten Pool

• 3D CLSVOF model simulates wide-band laser cladding melt pool dynamics. • Marangoni convection dominates flow, with high-speed zones around hot core. • Laser power critically affects temperature and morphology. • Model verified with average errors of 4.885% (width) and 7.043% (height). Wide-band laser cladding is an efficient surface strengthening and remanufacturing technology. In this paper, a three-dimensional transient numerical model was established by coupling the Level Set and VOF methods to simulate the temperature field, flow field and morphology evolution of the molten pool. Factors such as the laser heat source, powder addition, surface tension and buoyancy were comprehensively considered, and the infrared thermal imager was used for verification. The effects of laser power, scanning speed and powder feeding rate were systematically studied. The results show that the molten pool flow is mainly dominated by Marangoni convection, with high-temperature and low-speed in the center area and high-speed areas distributed around the high-temperature zone. The laser power has a significant impact on the temperature and size of the molten pool, and the molten pool temperature is negatively correlated with the scanning speed. The average comprehensive relative errors of the melt width and melt height are 4.885% and 7.043% respectively, it can effectively reflect the influence laws of process parameters on the morphology of the cladding layer.