1873K下鋼液中Ti-Al復合脫氧熱力學分析及夾雜物生成

Deoxidization thermodynamics of Ti-Al systems in molten steel at 1873K and precipitation of inclusions

摘要: 對1873K下鋼液中Ti-Al-O系復合夾雜物的形成進行了理論和實驗研究.理論計算和實驗結果表明,鋼液中Ti-Al-O系的Al-O基本趨于平衡,鋼液中自由氧由Al含量控制.Ti-Al-O系復合夾雜物的形成主要由a_Ti/a_Al值確定.根據熱力學數據計算得出了Ti-Al-O系復合夾雜物(Al₂O₃-Ti₃O₅-Ti₂O₃)的穩定區域;隨著a_Ti/a_Al的增加,夾雜物逐步由Al₂O₃轉變為Ti₃O₅夾雜物.當鋼液中自由氧含量較高時容易生成Ti₃O₅夾雜物.計算結果和觀察到的實驗結果一致.

Abstract: The thermodynamic analysis and experiments of inclusions formation in a Ti-Al-O system in molten steel at 1 873 K were investigated. The results show that in the Ti-Al-O system the equilibrium between Al and O can be obtained instantly and the content ofO is determined by the amount of Al. The formation of composite inclusions in the Ti-Al-O system depends on a_Ti/a_Al values. According to thermodynamic data, the stable section in the phase diagram of composite inclusions (Al₂O₃-Ti₃O₅-Ti₂O₃) in the Ti-Al-O system was calculated. The composition of inclusions changes from Al₂O₃ to Ti₃O₅ as the a_Ti/a_Al value increases. When the molten steel contains high amount ofO, it is very easy to form Ti₃O₅ inclusions. The experimental results agree well with thermodynamic data.