The present study was undertaken to investigate the evolution of inclusions in a Ti-containing Fe-25mass%Ni-15mass%Cr alloy during electroslag remelting (ESR). The effect of slag composition on the inclusions in alloy was studied. The inclusions in both consumable electrode and remelted ingots are mainly 1 to 3 µm in size. The inclusions in consumable electrode are TiN, Al₂O₃–Ti₂O₃, Al₂O₃–Ti₂O₃ with a surrounded TiN layer. The inclusions in liquid metal pool and remelted ingots are TiN, MgO–Al₂O₃–Ti₂O₃ inclusion surrounded by TiN, MgO·Al₂O₃ inclusions, MgO·Al₂O₃ inclusions with an outer Ti₂O₃-rich layer. Increasing TiO₂ content in slag has no influence on the types of inclusions in remelted ingots. The original TiN inclusions in consumable electrode cannot be dissociated at the electrode tip during the ESR process. TiN inclusions in remelted ingots mainly generated in liquid metal pool during ESR, and the TiN inclusions formed during the solidification of liquid alloy takes up a small amount fraction. Part of Al₂O₃–Ti₂O₃ inclusions in consumable electrode were removed through absorbing them into molten slag, and the remaining Al₂O₃–Ti₂O₃ inclusions in the liquid alloy reacted with Mg dissolved from ESR slag to form MgO–Al₂O₃–Ti₂O₃ inclusions which served as the nucleation sites for TiN inclusion formation. MgO·Al₂O₃ inclusions in the remelted ingots precipitated in the liquid metal pool during ESR process. The generation of MgO·Al₂O₃ inclusions with an outer Ti₂O₃-rich layer originated from the reaction between soluble titanium in liquid alloy and MgO·Al₂O₃ inclusion to form an outer Ti₂O₃-rich layer on unreacted MgO·Al₂O₃ inclusion core.

本研究旨在研究电渣重熔（ESR）过程中含Ti的Fe-25mass％Ni-15mass％Cr合金中夹杂物的演变。研究了炉渣成分对合金中夹杂物的影响。易耗电极和重熔铸锭中的夹杂物尺寸通常为1至3 µm。易耗电极中的夹杂物为TiN，Al ₂ O ₃ -Ti ₂ O ₃，Al ₂ O ₃ -Ti ₂ O ₃，周围有TiN层。液态金属熔池和重熔铸锭中的夹杂物为TiN，MgO–Al ₂ O ₃ –Ti ₂ O ₃TiN包围的MgO·Al ₂ O ₃夹杂物，MgO·Al ₂ O ₃夹杂物和富含Ti ₂ O _3的外层。炉渣中TiO ₂含量的增加对重熔铸锭中夹杂物的类型没有影响。在ESR过程中，可消耗电极中的原始TiN夹杂物无法在电极尖端解离。重熔铸锭中的TiN夹杂物主要在ESR期间在液态金属熔池中生成，而在液态合金凝固过程中形成的TiN夹杂物所占的份额很小。Al ₂ O ₃ -Ti ₂ O _{3的一部分}消耗电极中的夹杂物通过吸收进入熔融炉渣中而被去除，液态合金中剩余的Al ₂ O ₃ -Ti ₂ O ₃夹杂物与ESR炉渣中溶解的Mg反应形成MgO-Al ₂ O ₃ -Ti ₂ O ₃ TiN夹杂物形成的成核位点。在ESR过程中，重熔铸锭中的MgO·Al ₂ O ₃夹杂物沉淀在液态金属熔池中。外层Ti ₂ O ₃生成MgO·Al ₂ O ₃夹杂物富钛层源自液态合金中的可溶性钛与MgO·Al ₂ O ₃夹杂物之间的反应，从而在未反应的MgO·Al ₂ O ₃夹杂物芯上形成富Ti ₂ O ₃外层。