For high-power CO2 laser welding, besides two well known stable welding processes, i.e. stable deep penetration welding (DPW) and stable heat conduction welding (HCW), the authors have found the third welding process,...For high-power CO2 laser welding, besides two well known stable welding processes, i.e. stable deep penetration welding (DPW) and stable heat conduction welding (HCW), the authors have found the third welding process, i.e. unstable-mode welding (UMW) under the certain condition. UMW has its basic feature that the two welding modes (DPW and HCW) appear intermittently, with jumping of penetration depth and weld width between large and small levels. In this paper, effects of welding parameters (focal position, laser power and traveling speed) on laser welding mode and weld appearance have been comprehensively studied. Double-U curves of laser welding mode transition have been obtained, which indicate the ranges of the three mentioned welding processes. This work affords science foundation for selecting the welding process parameters correctly and obtaining stable laser welding.展开更多
A new current wave controlling method for short circuit transition CO 2 welding using saturable inductor is put forward in this paper. Theory analysis and experiment results prove that the inverter's dynamic char...A new current wave controlling method for short circuit transition CO 2 welding using saturable inductor is put forward in this paper. Theory analysis and experiment results prove that the inverter's dynamic characteristics is greatly improved, the declining speed of current during liquid bridge neck shrinking is quicker, subsequently the energy accumulated in the bridge and the radius of the bridge before rupturing is reduced thus the low spatter result is achieved.展开更多
文摘For high-power CO2 laser welding, besides two well known stable welding processes, i.e. stable deep penetration welding (DPW) and stable heat conduction welding (HCW), the authors have found the third welding process, i.e. unstable-mode welding (UMW) under the certain condition. UMW has its basic feature that the two welding modes (DPW and HCW) appear intermittently, with jumping of penetration depth and weld width between large and small levels. In this paper, effects of welding parameters (focal position, laser power and traveling speed) on laser welding mode and weld appearance have been comprehensively studied. Double-U curves of laser welding mode transition have been obtained, which indicate the ranges of the three mentioned welding processes. This work affords science foundation for selecting the welding process parameters correctly and obtaining stable laser welding.
文摘A new current wave controlling method for short circuit transition CO 2 welding using saturable inductor is put forward in this paper. Theory analysis and experiment results prove that the inverter's dynamic characteristics is greatly improved, the declining speed of current during liquid bridge neck shrinking is quicker, subsequently the energy accumulated in the bridge and the radius of the bridge before rupturing is reduced thus the low spatter result is achieved.
