Analysis on welding stability of twin deposition surfacing electrode

The influences of the electrode parameters and welding parameters on the welding stability were investigated with φ 4.0 mm twin deposition surfacing electrode. The results show that the arc voltage was mainly determined by the distance between twin cores, but it was also affected by the droplet transfer and arc force. Welding with too small or too large distance between twin cores degraded the welding stability. When the distance between twin cores was 1.0 mm and the arc voltage was kept at around 33 V, the welding process was stable. When the weight coefficient of the coating was 45%-56%, the hardness of the cladding layer was over 6200 MPa, with good protection and sufficient metallurgical reaction in the weld. The appropriate welding current should be controlled between 180-200 A, which was higher in magnitude but narrower in amplitude than that with traditional hard surfacing electrodes under the same specification. When the distance between the electrode and workpiece was 7 mm, excellent bonding between the weld and base metal was obtained with stable welding process.