Finite element simulation of vacuum arc remelting

Gartling, D. K.; Sackinger, Philip A.

doi:10.1002/(sici)1097-0363(199706)24:12<1271::aid-fld559>3.0.co;2-#

Cited by 7 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The following assumptions are made throughout this work: 1) The computational domain only includes the ingot. Current and heat enter the computational domain from the ingot top [ 17 ] ; 2) The molten steel is incompressible fluid, and the top surface of molten pool is flat and stationary; [ 18 ] 3) The melt rate is assumed to be constant, and the height of ingot is uniformly increased; 4) The inclusions are assumed to be stable and spherical, and there is no mass transfer between inclusions and molten steel. [ 19 ] Ignore the aggregation behavior of inclusions; and 5) Only inclusions brought into the molten pool by the droplets are considered in the model, and inclusions uniformly enter the molten steel from molten pool surface under the end of electrode.…”

Section: Numerical Model Descriptionmentioning

confidence: 99%

Motion Behavior of Ce‐Containing Inclusions in 8Cr4Mo4V‐Bearing Steel during Vacuum Arc Remelting

Pan,

Zhu,

Jiang

et al. 2024

steel research int.

View full text Add to dashboard Cite

Herein, the Ce‐containing inclusions in8Cr4Mo4V‐bearing steel are taken as the research objective to develop anumerical model of inclusions motions behavior. The model is validated bycomparing it with experimental data. During the vacuum arc remelting process, inclusions move along the molten pool's surface toward the edge under theaction of resultant force, and finally become trapped within the mushy zone. Notably, the majority of inclusions are concentrated near the ingot's edge, andtheir numbers decrease as the radial distance decreases. Furthermore, thenumber of Ce‐Mg‐O‐S inclusions exceeds that of Ce‐O‐S inclusions near the ingot's center. This discrepancy arises due to lower density of Ce‐Mg‐O‐Sinclusions, which exhibits a stronger tendency to migrate toward the moltenpool's center. Additionally, as the inclusion diameter increases, buoyancy forceacting on the inclusions increases, resulting in a higher number of inclusionsnear the ingot's center. When considering the effect of gas cooling, theinclusion distribution becomes more pronounced at the ingot's edge. This isattributed to the enhanced cooling capacity of the mold resulting in the decreasing of molten pool depth and consequently a stronger ability of themushy zone to trap inclusions.

show abstract

Section: Numerical Model Descriptionmentioning

confidence: 99%

Motion Behavior of Ce‐Containing Inclusions in 8Cr4Mo4V‐Bearing Steel during Vacuum Arc Remelting

Pan,

Zhu,

Jiang

et al. 2024

steel research int.

View full text Add to dashboard Cite

show abstract

“…To the best of the authors' knowledge, passive estimation of the current distribution during VAR (or other processes) from magnetic field measurements is a novel technique and has not yet been reported elsewhere. A number of studies have been published on VAR which focus on the effect that the current distribution has on the liquid metal flow in the melt pool and in the mushy zone using finite element methods [13] or finite difference/finite volume methods [14,15], showing its significance, but they do not discuss its measurement. It would be undesirable to use active sensing methods as the application of direct or alternating magnetic field and/or current can alter the flow patterns in the melt pool, leading to defects.…”

Section: Introductionmentioning

confidence: 99%

An analysis of the use of magnetic source tomography to measure the spatial distribution of electric current during vacuum arc remelting

Nair

Ward

2009

Meas. Sci. Technol.

View full text Add to dashboard Cite

Magnetic source tomography is explored to analyse the distribution of electric current during vacuum arc remelting (VAR). The goal is to use sensors outside the process to deduce the behaviour within. VAR systems having non-axisymmetric distributions of arc current were modelled using a commercial finite element electromagnetic code (Opera 3d), and a database was created from the resulting patterns of magnetic flux predicted to occur outside the crucible. A reconstruction algorithm was developed using constrained nonlinear optimization to estimate the arc current distribution within the process from the magnetic field data outside. The capabilities of this algorithm were studied, and it was found that given sufficiently low noise in the measurement data it was possible to accurately deduce important features of the spatial distribution of the arc current.

show abstract

Tree-ring formation during vacuum arc remelting of INCONEL 718: Part II. Mathematical modeling

Zhang

Lee

2002

Metall Mater Trans A

View full text Add to dashboard Cite

Tree-ring grain formations, a common microstructural feature found in vacuum arc remelted (VAR) ingots of nickel-based superalloys, were characterized experimentally in Part I. The experimental observations led to the conclusion that tree rings are chains of fine-equiaxed grains interrupting a predominately columnar-dendritic structure. Several possible mechanisms for their formation were considered, and their implications correlated with experimental observations. The most likely mechanism was determined to be that process perturbations cause changes in the thermal (or solutal) fields ahead of the columnar-dendrite tips, temporarily altering the conditions to increase grain nucleation and, hence, forming fine-equiaxed grains. In this article, Part II, a multiscale mathematical model of the VAR process is presented that simulates the macroscopic heat and momentum transport and combines it with a mesoscopic model of the nucleation and growth of grains. Using this multiscale model, the transient development of the VAR grain structure was simulated with varying levels and durations of fluctuations in the principal process parameters: power supply, arc focus, melt rate, and the ingot-crucible heat-transfer coefficient. The simulations were shown to agree with optical and electron back-scattered diffraction (EBSD) measurements of grain morphology and crystallographic orientation. The model results predict that tree-ring structures (consistent with those observed experimentally) can be formed by process perturbations that alter the thermal field conditions at the solidification front. A sensitivity study of the effect of the different process fluctuations on the microstructure formation was performed, providing process maps predicting the range of conditions where tree rings will not form.

show abstract

Finite element simulation of vacuum arc remelting

Cited by 7 publications

References 14 publications

Motion Behavior of Ce‐Containing Inclusions in 8Cr4Mo4V‐Bearing Steel during Vacuum Arc Remelting

Motion Behavior of Ce‐Containing Inclusions in 8Cr4Mo4V‐Bearing Steel during Vacuum Arc Remelting

An analysis of the use of magnetic source tomography to measure the spatial distribution of electric current during vacuum arc remelting

Tree-ring formation during vacuum arc remelting of INCONEL 718: Part II. Mathematical modeling

Contact Info

Product

Resources

About