(燕山大學(xué)國家冷軋板帶裝備及工藝工程技術(shù)研究中心，秦皇島 066004)
摘 要: 以薄帶鑄軋中心線偏析問題為研究對象，從宏觀和微觀角度分析鑄軋薄帶芯部偏析的成因與機(jī)理，建立完全耦合溶質(zhì)場、流場、溫度場的數(shù)學(xué)模型。通過數(shù)學(xué)模型對鑄軋鋁合金熔池中的Fe、Mn元素分布進(jìn)行研究。結(jié)果表明：理論研究與實(shí)驗(yàn)結(jié)果基本吻合。熔池區(qū)凝固組織以柱狀晶形式沿á001？方向迅速生長，同時溶質(zhì)成分逐漸偏聚于熔池芯部區(qū)域，并在Kiss點(diǎn)區(qū)域達(dá)到最大值。其中Fe元素在Kiss點(diǎn)區(qū)域的含量明顯高于其他區(qū)域的，完全凝固后易產(chǎn)生中心線偏析。隨著鑄軋速度的提高，輥縫寬度增大，中心線偏析趨勢增強(qiáng)。
關(guān)鍵字: 雙輥薄帶鑄軋；溶質(zhì)場；流場；中心線偏析；Kiss點(diǎn)
（National Engineering Research Center for Equipment and Technology of Cold Strip Rolling,
Yanshan University, Qinhuangdao 066004, China）
Abstract:The problem of casting Al-alloy strip was studied, the mechanism of as-cast strip centerline segregation was analyzed from the perspective of macro and micro, and a mathematical method was developed which completely couples solute field, flow field and temperature distribution. The distributions of Fe and Mn in the Al alloy molten pool were figured out by the mathematical method. The results show that the theoretical calculation agrees well with the experimental results. The solidification structure growsalongá001？ direction rapidly by the form of columnar crystal. Meanwhile, the solute elements are focused gradually in the kern zone, and the maximum value is gotten at the Kiss point zone. In particular, Fe content of the Kiss point zone is much higher than the average value, and centerline segregation appears after solidification. The centerline segregation tends to increase with the increase of casting speed and roll gap.
Key words: twin-roll strip casting; solute field; flow field; centerline segregation; Kiss point
