采用焊接电信号采集系统与高速摄像系统对SAF2507超级双相不锈钢CMT + P（冷金属过渡 + 脉冲）熔滴过渡过程进行观测研究. 分析了CMT与CMT + P过程在不同送丝速度WFS下的熔滴过渡行为、波形变化机理与能量输入特征，揭示了CMT + P熔滴过渡特性. 结果表明：CMT + P实际波形图与理论上有多处不同；熔滴形状与尺寸、过渡形式、熔池的波动状态、焊丝端部到工件的距离及飞溅等都能影响电压的波动，电压波形图可以用来指导分析熔滴过渡行为；脉冲阶段对热输入起主要影响作用，调节脉冲峰值电流、脉冲基值电流、脉冲个数，可实现热输入的控制.
In this paper, the high-speed camera and welding electrical signal collection system were applied to observe the metal transfer of CMT + P welding process in SAF2507 Super Duplex Stainless Steel. The metal transfer behaviors, change of waveforms and heat input characteristics with different WFS of CMT and CMT + P were analyzed. The droplet transfer characteristics were revealed. The results show that there are many differences between the actual waveforms and the theoretical waveforms. The shape and size of the droplet, transfer form, the wave state of molten pool, the distance from the wire tip to the workpiece and the spatter can all affect the fluctuation of the voltage. The voltage waveform diagram can be used to guide the analysis of the metal transfer behaviors. The pulse period plays a major role in heat input, and the control of heat input can be realized by adjusting pulse peak current, pulse base current and the number of pulses.
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