(1．昆明理工大學(xué) 冶金與能源工程學(xué)院，昆明 650093； 2. 中國科學(xué)院過程工程研究所，綠色過程與工程重點(diǎn)實(shí)驗(yàn)室，濕法冶金清潔生產(chǎn)技術(shù)國家工程實(shí)驗(yàn)室，北京 100190)
摘 要: 在1500 ℃下將Al-Si合金與CaO-SiO2-Al2O3熔渣混合精煉，考察了渣金比、精煉時(shí)間對(duì)體系中元素Al和B在渣金兩相間分配的影響，并解析了這兩種元素的遷移過程。結(jié)果表明：熔渣40%CaO-40%SiO2-20%Al2O3和60%Al-Si合金在渣金質(zhì)量比為5時(shí)，精煉硅中B含量由302.74×10-6降至23.37×10-6。元素Al和B在渣金兩相間的遷移規(guī)律基本一致，呈現(xiàn)出明顯的階段性特征。合金中Al元素在精煉10 min內(nèi)相間遷移最為劇烈，Al的轉(zhuǎn)化率達(dá)到96.52%，剩余少量Al以Al-Si相或Al-Si-Ca相存在于硅晶界處；而B元素在精煉30 min內(nèi)向渣中遷移效果最為顯著，遷移比分別為12.32、10.96，繼續(xù)延長時(shí)間二者含量均變化緩慢。Al元素的氧化會(huì)改變精煉渣的組成，精煉相同時(shí)間時(shí)，隨渣中w(CaO+Al2O3)/w(SiO2)值增大，精煉硅中B含量呈先下降后上升的趨勢(shì)，B含量在w(CaO+Al2O3)/w(SiO2)值1.24附近有最小值8.01×10-6，此時(shí)B的遷移比達(dá)到37.80。
關(guān)鍵字: 鋁硅合金；B；造渣精煉；遷移；分配
（1. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kuming 650093, China; 2. National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China）
Abstract:Al-Si alloy and CaO-SiO2-Al2O3 slag were mixed and refined at 1500 ℃. The effects of ratio of slag to metal, refining time on the distribution of Al and B in the system between the slag and metal phase were investigated. Also, the migration process of Al and B in the system was analyzed. The results show that, the B content in the refining Si decreases from 302.74×10-6 to 23.37×10-6, when the ratio of 40%CaO-40%SiO2-20%Al2O3 slag to 60% Al-Si alloy is 5. The migration patterns between the slag and metal phase of Al and B are almost the same, both of which change with stages. For Al, it is the most violent in the first 10 min, the transformation rate of Al reaches up to 96.52%, and the remaining amount of aluminum exists at the silicon grain boundary in the form of Al-Si phase or Al-Si-Ca phase. While for B, the most violent migration into slag happens in the first 30 min. And their migration ratios (Rm) are 12.32 and 10.96, respectively. Further increasing time will only bring a slow change of their content. The refining slag is changed by the oxadation of Al, and Al content will be enhanced with the increase of w(CaO+Al2O3)/w(SiO2) under the same refining time. However, B content decreases at first and then increases, whose minimum value is 8.01×10-6 when w(CaO+Al2O3)/w(SiO2) is 1.24, and now the migration ratio of B is 37.80.
Key words: Al-Si alloy; boron; slag refining; migration; distribution
