界面反应调控颗粒增强6061铝合金中碳化硅的超重力分离  

High-gravity separation of silicon carbide in particle-reinforced 6061 aluminum alloy through interfacial reaction control

作　　者：庞昇 王志[1,2,3] 李世健[1,2] 孙义伟 钱国余 王东 PANG Sheng;WANG Zhi;LI Shi-jian;SUN Yi-wei;QIAN Guo-yu;WANG Dong(Key Laboratory of Green Process and Engineering,National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;Innovation Academy for Green Manufacture,Chinese Academy of Sciences,Beijing 100190;School of Chemical Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院过程工程研究所,湿法冶金与清洁生产技术国家工程实验室,中科院绿色过程与工程重点实验室,北京100190 [2]中国科学院绿色过程制造创新研究院,北京100190 [3]中国科学院大学化学工程学院,北京100049

出　　处：《矿冶》2021年第3期7-11,共5页Mining And Metallurgy

基　　金：国家重点研发计划项目(2018YFC1901801);国家自然科学基金资助项目(U1702251);北京市自然科学基金资助项目(2192055)。

摘　　要：将废旧铝合金循环利用制备再生铝对缓解资源压力和节能环保都有重要意义,可有力地推动铝合金制造业的绿色可持续发展。而颗粒增强的铝合金基体中弥散且均匀地分布着大量微米级颗粒(碳化硅、氧化铝等),常规分离手段难以实现其高效富集。超重力分离利用了熔体与夹杂物密度的差异,在金属熔体提纯和非金属夹杂物去除等领域已得到较为广泛的研究。但由于增强颗粒SiC与铝合金熔体界面反应较为容易,低密度的反应物产物Al4C3包裹于SiC颗粒上,极大地缩小了增强颗粒与铝合金熔体间的密度差,增加了分离难度,因此如何控制界面反应对分离至关重要。界面反应的发生与温度及反应物浓度密切相关,而该体系中反应物浓度保持不变,通过控制温度可实现对界面反应的调控。为了研究温度对分离的影响,重力系数G保持不变,将增强颗粒作为合金中的夹杂物,以碳化硅增强的6061铝合金为实验原料进行了超重力分离实验。结果表明,在重力系数G=800、反应温度为670℃条件下,10 min内实现了增强颗粒与合金基体的高效分离。本研究可为其它增强体合金的循环再生提供典型范例。The recycling of end-of-live aluminum alloys to produce secondary aluminum is of great significance to alleviating resource pressure,energy conservation and environmental protection,which can effectively promote the green and sustainable development of aluminum alloy manufacturing.However,a large number of micron-sized particles(SiC,Al 2 O 3,etc.)are dispersed and evenly distributed in the particle-reinforced aluminum alloy matrix,and it is difficult to achieve high-efficiency enrichment by conventional separation methods.High gravity separation takes advantage of the difference in density between melt and inclusions,which has been extensively studied in the fields of metal melt purification and non-metallic inclusion removal.However,since the reinforcing particle SiC is more likely to react with aluminum alloy melt,the low density reactant product Al 4C 3 will wrapped on SiC particles,which greatly reduces the difference in density between the reinforcing particles and the aluminum alloy melt,and increases the separation difficulty.Therefore,how to control interface reactions is critical to separation.The occurrence of the interface reaction is closely related to the temperature and reactant concentration.But the concentration of the reactant in the system remains unchanged,thus,the regulation of the interface reaction can be achieved by controlling the temperature.In order to study the effects of temperature on phase separation,the gravity coefficient G remains unchanged,the reinforced particles are used as the inclusions in the alloy,and the 6061 aluminum alloy reinforced with silicon carbide was used as the experimental raw material.When the coefficient of gravity is 800 and the reaction temperature is 670 ℃,the efficient separation of the reinforcement particles and the alloy matrix is achieved within 10 min,which provides a typical example for the recycling of other reinforcement alloys.

关 键 词：颗粒增强 6061铝合金 碳化硅 超重力分离 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TB32[金属学及工艺—金属材料]