Abstract: In this paper， the effects of two types of electroslag remelting slag systems on the content of the quantity， size， and distribution of inclusions in C-HRA-3 heat-resistant alloy electroslag ingots was investigated by using a 10 kg level protective atmosphere electroslag remelting furnace. The results show that the liquidus temperature of 60% CaF₂-20% Al₂O₃-10% CaO-10% MgO based slag system is 1 417 ℃， the liquidus temperature of new type 50.4% CaF₂-26.1% Al₂O₃-19.5% CaO-4% MgO based slag system is 1 324 ℃ and the new type slag system has a narrow temperature range between solidus and liquidus， and the resistivity of liquid slag is high， which can ensure the high melting rate and stable smelting of C-HRA-3 alloy electroslag remelting. The inclusions in the electroslag ingots produced by two slag systems mainly include oxides， carbonitrides， and sulfides. The number of inclusions at the edge of the electroslag ingots is similar to that of the consumable electrode， and the number of inclusions from the edge to the center of the electroslags shows a gradually decreasing trend. Moreover the average size of oxide inclusions in electroslag ingots smelted with two slag systems is respectively 3.019 μm and 2.341 μm. Along different radial positions of the new type slag system smelting electroslag ingot， the proportion of oxide inclusions with size > 3 μm is smaller， which has a more significant removal effect on large-sized oxide inclusions in C-HRA-3 alloy.

Key words: Electroslag Remelting, Slag System, C-HRA-3 Heat Resistant Alloy, Inclusions

摘要： 本文利用10 kg级保护气氛电渣重熔炉，研究了两种电渣重熔渣系对C-HRA-3耐热合金电渣锭夹杂物数量、尺寸、分布规律的影响。结果表明，60%CaF₂-20%Al₂O₃-10%CaO-10%MgO渣系的液相线温度为1417 ℃，新型50.4%CaF₂-26.1%Al₂O₃-19.5%CaO-4%MgO渣系的液相线温度为1324 ℃，且固液两相区的温度区间较窄，液态熔渣的电阻率高，可实现C-HRA-3合金电渣重熔的高熔速稳定冶炼。两种渣系冶炼的电渣锭中，夹杂物主要包括氧化物、碳氮化物和硫化物等类型，电渣锭边缘位置夹杂物数量与自耗电极相近，电渣锭边缘到中心位置夹杂物数量呈现出逐渐减少的趋势。两种渣系冶炼的电渣锭中，氧化物夹杂的平均尺寸分别为3.019 μm和2.341 μm。新型渣系冶炼的电渣锭中，沿径向不同位置处，尺寸＞3 μm的氧化物夹杂数量占比均更小，对C-HRA-3合金大尺寸氧化物夹杂具有更显著的去除效果。

关键词: 电渣重熔, 渣系, C-HRA-3耐热合金, 夹杂物