電渣重熔過程中渣成分變化及鋼中氧含量預測

  電(dian)渣(zha)(zha)(zha)重(zhong)(zhong)(zhong)熔(rong)具有(you)工藝穩定、過(guo)程(cheng)可控(kong)(kong)制(zhi)以(yi)及冶金(jin)質(zhi)量(liang)優(you)良等優(you)點,成為現代冶金(jin)的(de)一個(ge)重(zhong)(zhong)(zhong)要熔(rong)煉(lian)方(fang)法(fa),特別是(shi)在航天航空材料制(zhi)造等特殊行(xing)業方(fang)面應用廣泛。電(dian)渣(zha)(zha)(zha)重(zhong)(zhong)(zhong)熔(rong)過(guo)程(cheng)中(zhong),渣(zha)(zha)(zha)系的(de)組成是(shi)整個(ge)控(kong)(kong)制(zhi)過(guo)程(cheng)的(de)核心部分,對電(dian)渣(zha)(zha)(zha)重(zhong)(zhong)(zhong)熔(rong)鋼錠的(de)質(zhi)量(liang)起著決(jue)定性作用。電(dian)渣(zha)(zha)(zha)重(zhong)(zhong)(zhong)熔(rong)過(guo)程(cheng)中(zhong)爐渣(zha)(zha)(zha)成分隨時間的(de)變(bian)化(hua)必然影響(xiang)到電(dian)渣(zha)(zha)(zha)的(de)黏度,電(dian)導率等物理化(hua)學性質(zhi)和冶金(jin)性能,進而對重(zhong)(zhong)(zhong)熔(rong)過(guo)程(cheng)產生(sheng)影響(xiang)。

  科研工作者利用(yong)XRF和(he)XRD技術分(fen)析(xi)(xi)了電渣(zha)重(zhong)熔過(guo)程中(zhong)(zhong)(zhong)不同時(shi)間所取渣(zha)樣的(de)化(hua)(hua)學成分(fen)和(he)物(wu)相結構(gou)。XRF分(fen)析(xi)(xi)得到電渣(zha)重(zhong)熔過(guo)程中(zhong)(zhong)(zhong)渣(zha)中(zhong)(zhong)(zhong)Al2O3、CaF2、CaO、SiO2、FeO等(deng)成分(fen)含量隨(sui)熔煉時(shi)間的(de)動(dong)態變(bian)化(hua)(hua)。XRD分(fen)析(xi)(xi)表明:凝固的(de)渣(zha)中(zhong)(zhong)(zhong)存(cun)在11CaO·7Al2O3 ·CaF2、12CaO·7Al2O3、CaSiO3等(deng)高熔點物(wu)質(zhi)(zhi),導致爐渣(zha)性質(zhi)(zhi)發生(sheng)變(bian)化(hua)(hua)。根(gen)據(ju)熔渣(zha)化(hua)(hua)學成分(fen),參考CaF2-CaO-Al2O3渣(zha)系的(de)等(deng)電導率(lv)圖和(he)等(deng)黏(nian)度(du)圖,得到了電渣(zha)的(de)比電阻和(he)黏(nian)度(du)隨(sui)冶煉時(shi)間的(de)變(bian)化(hua)(hua)情(qing)況。采用(yong)爐渣(zha)結構(gou)共(gong)存(cun)理論建立(li)了溫度(du)為1923K和(he)1973K時(shi)與渣(zha)中(zhong)(zhong)(zhong)Al2O3平衡的(de)鋼液中(zhong)(zhong)(zhong)[Al]-[O]平衡關系圖。

  結果顯示,針(zhen)對(dui)實驗研究的(de)鋼種,當鋼中酸溶(rong)鋁(lv)含量ω[Al]s在0.0001%~1%范圍內時(shi),鋼液中溶(rong)解氧含量隨著(zhu)ω[Al]s的(de)增(zeng)加先減(jian)小后增(zeng)大,當鋼中ω[Al]s達到0.25%時(shi),鋼液中ω[O]最小。在實驗條(tiao)件下(xia),因渣成(cheng)分(fen)變化(hua)導致的(de)鋼中ω[O]的(de)波動范圍是0.25%×10-6~0.48×10-6。