Gain refinement in metal alloy can be achieved by applying an electric current pulse (ECP) in solidification process. Forced flow inside the melt has been proved to be a key role in grain refinement. In this paper, the fluid flow inside Ga 20 wt%–In 12 wt%–Sn alloy induced by a damping sinusoidal ECP flowing through two parallel electrodes into the cylindrical melt was investigated by both experimental measurements and numerical simulations. Experimental results showed that a strong descending jet was induced beneath the bottom of electrodes under the application of ECP. Besides, it was found that flow intensity increases with the increase of amplitude, frequency, and pulse width, respectively. In order to unlock the formation mechanism of flow pattern and the relevance of flow intensity varied with electrical parameters, a three-dimensional numerical model under the application of ECP was established. Meanwhile, a comparative study was conducted by numerical simulations to reveal the distributions of electromagnetic fields and forced flow. Numerical results showed that the downward Lorentz force induced by ECP was concentrated beneath the bottom of electrodes. This downward Lorentz force induces a descending jet and provokes a global forced flow. According to numerical simulations, the evolution of flow intensity with electrical parameters under the application of ECP can be understood by the time averaged impulse of Lorentz force.

通过在凝固过程中施加电流脉冲 (ECP) 可以实现金属合金的增益细化。熔体内部的强制流动已被证明是晶粒细化的关键作用。在本文中，通过实验测量和数值模拟研究了由阻尼正弦 ECP 流过两个平行电极进入圆柱形熔体引起的 Ga 20 wt%-In 12 wt%-Sn 合金内部的流体流动。实验结果表明，在ECP作用下，在电极底部下方产生了强烈的下降射流。此外，发现流动强度分别随着振幅、频率和脉冲宽度的增加而增加。为了解开流型的形成机制以及流动强度随电参数变化的相关性，建立了ECP应用下的三维数值模型。同时，通过数值模拟进行了对比研究，揭示了电磁场和强迫流的分布。数值结果表明，ECP 引起的向下洛伦兹力集中在电极底部下方。这种向下的洛伦兹力引起下降的射流并引发全球强制流动。根据数值模拟，可以通过洛伦兹力的时间平均脉冲来理解在ECP应用下流动强度随电参数的演变。数值结果表明，ECP 引起的向下洛伦兹力集中在电极底部下方。这种向下的洛伦兹力引起下降的射流并引发全球强制流动。根据数值模拟，可以通过洛伦兹力的时间平均脉冲来理解在ECP应用下流动强度随电参数的演变。数值结果表明，ECP 引起的向下洛伦兹力集中在电极底部下方。这种向下的洛伦兹力引起下降的射流并引发全球强制流动。根据数值模拟，可以通过洛伦兹力的时间平均脉冲来理解在ECP应用下流动强度随电参数的演变。