超重力分离法净化2011型号废旧Al-Cu合金
Supergravity purification and regeneration of waste Al-Cu alloy
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摘要: 基于Al-Cu合金中不同杂质相的熔点差异,借助超重力场可强化过滤分离的特点,以2011型号Al-Cu合金为原料,探究合金中杂质元素Fe、Pb和有益元素Al、Cu的分离规律。研究结果表明:原料经过高温重熔再结晶的过程后,杂质聚集到铝基体晶界间,在高温超重力场中,低熔点杂质可穿过晶界间的孔隙分离除去,当超重力分离时间≥1 min时,Fe、Pb含量不再随时间变化;提高超重力系数和温度均有利于Fe、Pb的去除,但Al、Cu回收率降低。综合考虑Fe、Pb含量和Al、Cu回收率,确定较好的超重力分离工艺参数:超重力系数为600、分离温度为610 ℃、分离时间为1 min,该工艺参数条件下,Fe、Pb含量分别净化至0.06%和0.08%,Al、Cu回收率分别为95.64%、67.90%,废旧Al-Cu合金中的Al和Cu总占比由97.91%提升至99.72%。Abstract: In this paper, based on the difference in melting points of different impurity phases in 2011 Al-Cu alloy, the separation law of impurity elements Fe and Pb and beneficial elements Al and Cu in the alloy was investigated with the help of the feature of enhanced filtration and separation in the supergravity field. The results show that the impurities in raw materials after the high-temperature remelting and recrystallization processes gather between the grain boundaries of the aluminum matrix. In the high-temperature supergravity field, low-melting-point impurities could be separated and removed through the pores between the grain boundaries, and when the supergravity separation time is ≥ 1 min, the Fe and Pb content no longer changes with time. Increasing the supergravity coefficient and temperature are conducive to the removal of Fe and Pb, but the recovery of Al and Cu is reduced. Taking into account the content of Fe and Pb, as well as the recovery rates of Al and Cu, the optimal parameters for the supergravity separation process are determined as follows: a supergravity coefficient of 600, a separation temperature of 610°C, and a separation time of 1 min. Under these parameters, the Fe and Pb contents are purified to 0.06% and 0.08%, respectively. The recovery rates of Al and Cu recoveries are 95.64% and 67.90%, respectively, and the scrap Al -Cu alloy in the total percentage of Al and Cu from 97.91% to 99.72%.