GH4698合金真空电弧重熔过程中熔池流动形态

Molten Pool Flow Morphology during Vacuum Arc Remelting Process for GH4698 Alloy

摘要:

为了进一步了解真空电弧重熔(VAR)过程，本文利用开源CFD计算软件OpenFOAM，基于有限体积法(FVM)建立了包括电磁场、温度场和流场的二维多场耦合模型来研究宏观非稳态下的GH4698镍基合金铸锭的凝固过程。结果表明，从坩埚流向自耗电极的电流所引发的磁场主要集中在铸锭的上部，并沿铸锭轴线旋转。磁感应强度由铸锭中心向边缘呈现先增大后减小的趋势，并在电极边缘处达到最大值。热浮力和洛伦兹力是熔池内的主要驱动力，并且它们对熔池流动的影响正好相反。

Abstract:

In order to further understand the Vacuum arc remelting(VAR) process, with the help of OpenFOAM, an open source CFD computing software, a two-dimensional multi-physical finite volume model (FVM) including electromagnetic field, temperature field and flow field was established to study the macroscopic phenomenon of the unsteady solidification process on GH4698 nickel-based super alloy ingots. Results shows that magnetic induction intensity induced by the current flowing from the crucible to the consumable electrode is mainly concentrated on the upper part of the ingot and rotates along the axis of the ingot. The magnetic induction intensity first increases and then decreases from the center to the edge of the ingot, and reaches the maximum value at the edge of the electrode. Thermal buoyancy and lorentz forces are the main driving forces in the molten pool and their effect on the flow of molten pool is opposite to each other.