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基于ANSYS有限元软件建立了钒合金电子束熔炼过程的数理模型,对V-4Cr-4Ti合金电子束熔炼过程进行了数值模拟,研究了不同熔炼工艺参数下的熔炼过程温度场分布规律以及熔池形状。结果表明:熔炼过程温度场分布及熔池形状受到熔炼功率及扫描半径的影响。随着熔炼功率的增大,熔池最高温度将会线性增大,熔池宽度和深度将会逐渐增大。随着扫描半径的增大,熔池最高温度将会先增大后减小,通过分析获得了V-4Cr-4Ti合金电子束熔炼的最佳工艺参数。实验结果表明,在优化后的工艺条件下,钒合金电子束熔炼铸锭质量得到一定提升。 相似文献
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电渣熔铸过程中熔渣的流动决定了熔铸体系温度场的分布以及金属熔池的形状,最终影响熔铸钢锭的质量。采用大型通用有限元分析软件ANSYS,对电渣熔铸体系渣池流场进行了模拟研究,所得结果与物理模拟实验结果完全一致。并以此研究了熔铸电流,填充比和电极端部形状对熔渣流速分布的影响,为实际生产提供了依据。 相似文献
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本文运用有限元方法对不同频率下电磁搅拌辅助装置中心处磁场强度以及熔池电磁力进行了模拟分析,并研究了旋转磁场对熔池电磁力和熔池温度分布及流场影响,结果表明当电流频率增大时,熔池中电磁力首先有缓慢减小趋势,同时功率损耗迅速增大,当频率继续增大时,电磁力逐渐增大,此时功率损耗基本趋于稳定;在激励电流变化的一个周期内,搅拌装置中磁场强度也发生周期性变化。在施加旋转磁场条件下,熔池整体温度有所降低,温度梯度减小,熔池内形成围绕熔池做周向流动的环流,流速分布均匀。 相似文献
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《稀有金属材料与工程》2016,(7)
运用有限元方法对不同频率下电磁搅拌辅助装置中心处磁场强度以及熔池电磁力进行了模拟分析,并研究了旋转磁场对熔池电磁力和熔池温度分布及流场影响。结果表明,当电流频率增大时,熔池中电磁力首先有缓慢减小趋势,同时功率损耗迅速增大,当频率继续增大时,电磁力逐渐增大,此时功率损耗基本趋于稳定;在激励电流变化的一个周期内,搅拌装置中磁场强度也发生周期性变化。在施加旋转磁场条件下,熔池整体温度有所降低,温度梯度减小,熔池内形成围绕熔池做周向流动的环流,流速分布均匀。 相似文献
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《金属学报》2017,(4)
基于多物理场耦合计算,结合电渣重熔(ESR)工艺,开发了应用于ESR全过程数值模拟的数学模型。模型涵盖了熔炼过程的电磁场、流动、传热、熔化及凝固多个物理过程,给出了熔炼过程温度及液相体积分数分布、熔池及糊状区形状尺寸等过程控制所相关的特征信息。利用铸锭温度分布历史,该模型可以计算与铸锭质量密切关联的多种凝固参数信息。该模型可以实现对未知ESR过程的稳态模拟预测,也可以针对实际过程进行熔炼全程(包括模冷阶段)的瞬态模拟分析。模型计算的熔池形状及深度与剖锭分析的结果接近,预测的二次枝晶臂间距分布与枝晶组织分析照片相符合。本模型可应用于过程分析及优化,并为新产品和工艺研发提供重要的技术支撑。 相似文献
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Further research on metallic materials for the super critical rotator and the main pipe line of a nuclear power station is very important for developing the nuclear power industry.In this study,the mathematical model for 120 t large ingot was established,and the computer program ESR3D was developed to simulate the whole electroslag re-melting (ESR) process.This includes the electrode melting,metallic droplet falling,metal pool forming,metal pool and slag pool rising and moving,installation of top crystallizer,ingot solidifying,etc.The simulated average melting rate of the electrode was in good agreement with that in practical production.The optimized parameters were used to produce 80-120 t large ingots,and the quality of the ingots satisfied the specifications of nuclear power and the super critical generating unit. 相似文献
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电渣重熔体系内磁场的数学模拟 总被引:5,自引:0,他引:5
基于Maxwell方程组及有关的电磁场理论,提出了更切合实际情况的电渣重熔体系内磁场的数学模型,并应用于结晶器直径200mm的实验室重熔装置.对直径76mm低碳低合金钢电极的重熔过程(3000A(有效值),CaF2+30mass%Al2O3+20mass%CaO渣系),结果表明,磁场强度的幅模在电极内沿端部锥体形成方向不断增大,至接近锥顶处达最大值,约为2.6×104A/m,此后在渣池、锭子熔池、液固两相区和固态锭子内沿轴向向下逐渐减小;沿半径方向,在电极和渣池内呈现一峰值,在液、固金属区内则单调增大至边界条件限定值.对在直径140mm的结晶器中以直径80mm的电极和CaF2+CaO+Al2O3+MgO渣系生产高速钢(M2)锭的过程,以该模型估计的重熔体系渣池和金属熔池内磁场强度(幅模)的大小和分布与实测结果较相吻合.该模型可作为研究电渣重熔体系内熔体流动,传热和传质过程的基础. 相似文献
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Formation mechanism of shrinkage and large inclusions of a 70t 12Cr2Mo1 heavy steel ingot简 总被引:1,自引:0,他引:1
Shrinkage cavities and large inclusions are serious internal defects of heavy steel ingot and influence the quality of subsequent forgings.In order to remove these two types of defects,a 70 t 12Cr2Mo1 heavy ingot fabricated by vacuum carbon de-oxidation process was sectioned and investigated by means of structure observation and EDS analysis.To further study the forming mechanism of shrinkage and inclusion defects and find possible solutions,simulation on pouring and solidification processes was also carried out using Fluent and ProCAST software,respectively.Results show that the shrinkage defects do not appear in the middle-upper part of the ingot.The critical value of shrinkage cavity criterion is ascertained as 0.013 on the basis of sectioning investigation and simulation results,which can be used in computer simulation to predict and avoid shrinkage defects in production of 12Cr2Mo1 ingots with different weights.However,large inclusions are found at the bottom of the ingot body.The bad thermal conditions of the ingot surface and large amount of entrained slag are the main origin of the large inclusions.The simulation result of the pouring process shows that large inclusions may be eliminated by combined measures of improving the top thermal condition and controlling the height of rudimental molten steel in the ladle to above 300 mm. 相似文献
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李莹莹 《特种铸造及有色合金》2020,(3):324-326
针对真空自耗熔炼大规格(?≥760mm)钛合金铸锭易出现头部缩孔较深、切头量大的问题,分析了缩孔产生的原因,论述了热封顶工艺制定的原则和方法,并据此制定了适合实际生产的热封顶工艺制度。试生产发现,该工艺可显著减小缩孔深度,提高铸锭的成品率。 相似文献
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In the electroslag remelting process, the electrode molten state is a critical factor determining the ingot quality, while the electrode immersion depth and melting rate are key factors for the stability of the electroslag re-melting process. Studies were carried out to investigate the microscopic and macroscopic effects of electrode immersion depth and melting rate on the potential distribution and heat density in the slag bath, and on the depth and shape of the molten bath. Based on the finite element method and the numerical solution method, the effect of the electrode immersion depth on the slag bath heat density was researched; the relationship between the electrode immersion depth and the slag resistance was obtained; and the unsteady-state model of the solidification process of the re-melting ingot was solved using the finite difference method. The mathematical model and physical model of the electrode melting process were established and solved; and the corresponding curves between the electrode molten-state and slag-bath physical parameters were obtained. The experimental results verified the simulated results studied in this paper. 相似文献
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The electrode configuration determines the thermophysical field during the electroslag remelting(ESR) process and affects the final microstructure of the ingot. In this work, ingot with a diameter of 400 mm was prepared with two electrode configuration modes of single power ESR process, namely one electrode(OE) and two series-connected electrodes(TSCE). Finite element simulation was employed to calculate the electromagnetic field, flow field and temperature field of the ESR system. The results show that the temperature of the slag pool and the metal pool of the TSCE process is lower and more uniform than that of the OE process.The calculated temperature distribution of the ingot could be indirectly verified from the shape of the metal pool by the experiment. The experimental results show that the depth of the metal pool in the OE ingot is about 160 mm, while the depth of the TSCE ingot is nearly 40 mm shallower than that of the OE ingot. Microstructural comparisons indicate that coarse eutectic carbides are formed in the center of the OE ingot, whereas more even eutectic carbides appear in the center of the TSCE ingot. In general, compared with the OE process, the TSCE process is preferred to remelt high speed steel ingots. 相似文献
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Mn18Cr18N护环钢电渣重熔工艺的研究 总被引:1,自引:0,他引:1
通过对10t电渣炉电气特性的分析,确定了渣池输入功率最大时的临界电流值。理论分析了供电制度、电极直径、渣系和钢种对电渣重熔钢锭表面质量的影响机理。钢锭侧面凝固前沿位置即金属熔池具有无圆柱部分是判断电渣锭表面质量优劣的基本依据。工业试验和理论分析阐明了改善Mn18Cr18N电渣重熔钢锭表面质量的主要措施,并提出了合理的重溶工艺制度。 相似文献