Abstract:  GH4151 is a high-performance precipitation strengthened new nickel-based high temperature alloy， suitable for the manufacture of aviation engine turbine disc forgings. Based on the industrially validated MeltFlow software， the effects of different smelting process parameters on the electroslag remelting process of GH4151 alloy were studied. The results revealed with the process of the electroslag remelting， the morphology distribution of the molten pool exhibited a deep central region and shallow periphery at different smelting stages. Ultimately， the melt pool solidified at the center of the slag pool-liquid metal interface. ；As the melt speed was increased from 1.5 kg/min to 4.5 kg/min， the maximum depth of the melt pool increased from 360 mm to 474 mm， and the maximum width of the paste zone expanded from 60 mm to 99 mm. Furthermore， the local solidification time， the spacing of secondary dendrites， and the probability of black spot formation all exhibited a notable increase. As the electrode diameter increased （with the filling ratio rising from 0.27 to 0.94）， the depth of the melt pool and the width of the mushy zone showed no change. However， the volume of the melt pool decreased by 0.001 5 m³， and the thickness of the slag skin reduced by approximately 1 mm. The probability of black spot formation and the local solidification time both decreased as the electrode diameter increased. Therefore， the melting speed should have been reduced， and the electrode diameter （filling ratio） should have been increased， which would have been more favorable for the solidification quality of alloy.

Key words: GH4151 Alloy, Electroslag remelting, Melting speed, Filling Ratio

摘要： GH4151是一种高性能沉淀强化的新型镍基高温合金，适合用于航空发动机涡轮盘锻件的制造。基于经过工业验证的MeltFlow软件，研究了不同熔炼工艺参数对GH4151合金电渣重熔过程的影响。结果表明，随着电渣重熔的进行，不同冶炼时刻熔池形貌分布为整个熔池呈现中心深，周围浅，熔池最后凝固在渣池-金属液交界面中心处。随着熔速增加（1.5~4.5 kg/min），熔池最大深度从360 mm增加到474 mm，糊状区最大宽度从60 mm增加至99 mm，同时，局部凝固时间、二次枝晶间距和黑斑形成概率皆增大；随着电极直径增加（填充比从0.27增加至0.94），熔池深度和糊状区宽度变化不大，但熔池体积减小了0.001 5 m3，渣皮厚度减小了约1 mm。黑斑形成概率和局部凝固时间随着电极直径增加均减小。因此，应适当减小熔速，增大电极直径（增大填充比），对合金凝固质量更有利。

关键词: GH4151合金, 电渣重熔, 熔速, 填充比