A comprehensive three-dimensional transient computational fluid dynamics(CFD)model was developed to ana-lyze the thermophysical phenomena in the arc wire additive manufacturing(WAAM)process.The model includes droplet ...A comprehensive three-dimensional transient computational fluid dynamics(CFD)model was developed to ana-lyze the thermophysical phenomena in the arc wire additive manufacturing(WAAM)process.The model includes droplet impact,gravity,heat and mass transfer,molten metal flow,and solid-liquid phase changes.By integrating the mass,energy,momentum,and volume of fluid(VOF)equations,a layer-by-layer additive process was suc-cessfully simulated.The accuracy of the model was validated by comparing the simulation results of single-pass single-layer weld beads at three welding positions with experimental data.The established model was utilized to quantitatively investigate the effects of three crucial welding process parameters-welding direction,droplet transfer frequency,and initial temperature-on the multi-layer cladding process.These findings suggest that the use of opposite welding directions in two adjacent layers can result in a well-distributed overall morphology of the weld bead.Moreover,the high initial droplet temperature enhanced the inclination of the weld bead mor-phology while decreasing the height of each layer.However,the high droplet transfer frequency caused both the height and width of the weld to increase.This research contributes to explaining the formation mechanism of the multi-layer cladding process and offers insights for improving weld bead morphology.This provides valuable theoretical guidance for the process optimization and control of arc additive manufacturing technology.展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.52076216,51706246).
文摘A comprehensive three-dimensional transient computational fluid dynamics(CFD)model was developed to ana-lyze the thermophysical phenomena in the arc wire additive manufacturing(WAAM)process.The model includes droplet impact,gravity,heat and mass transfer,molten metal flow,and solid-liquid phase changes.By integrating the mass,energy,momentum,and volume of fluid(VOF)equations,a layer-by-layer additive process was suc-cessfully simulated.The accuracy of the model was validated by comparing the simulation results of single-pass single-layer weld beads at three welding positions with experimental data.The established model was utilized to quantitatively investigate the effects of three crucial welding process parameters-welding direction,droplet transfer frequency,and initial temperature-on the multi-layer cladding process.These findings suggest that the use of opposite welding directions in two adjacent layers can result in a well-distributed overall morphology of the weld bead.Moreover,the high initial droplet temperature enhanced the inclination of the weld bead mor-phology while decreasing the height of each layer.However,the high droplet transfer frequency caused both the height and width of the weld to increase.This research contributes to explaining the formation mechanism of the multi-layer cladding process and offers insights for improving weld bead morphology.This provides valuable theoretical guidance for the process optimization and control of arc additive manufacturing technology.
