Abstract: The dynamic process of rotating transfer undergoing the longitudinal magnetic field control is discussed,and the formation of circum current is analyzed because of the rotating of the liquid streaming.The process of rotating transfer is affected by the interaction of the circum current and the additional longitudinal magnetic field.The experimental results show that the process of rotating transfer can be controlled by the additional longitudinal magnetic field.Under the shielding gas of 80% Ar+20% CO₂,a stable and better controlled rotating transfer is realized with the wire feed speed of 45 m/min.Thus the melting efficiency of the welding materials increases obviously.In this case,a new metal active gas welding process with higher performance and less cost is realized under the condition of the continuous and high current with the common shielding gas free of helium.