电火花法制备高纯超细氧化铝粉末

发布时间：2018-03-02 06:41

  本文关键词： 电火花 电蚀量 氢氧化铝 α-Al_2O_3　出处：《西安建筑科技大学》2010年硕士论文　论文类型：学位论文

【摘要】： 本文对电火花法制备高纯超细氧化铝进行了系统的研究,采用很安全的低压直流电源进行放电实验,制备出了高纯超细氧化铝,并得出以下结论： 以不同纯度金属铝在二次去离子水中火花放电制备出以Al(OH)3和Al为主的前驱体,二者之外的杂质主要取决于原料铝的纯度,火花放电过程不会造成新的污染。 研究了火花放电机理,发现残留铝的含量主要取决于间断放电电蚀量,间断放电电蚀量又取决于间断放电能量,间断放电能量的大小取决于电压,电流,脉冲宽度等因素。对放电后铝粒表面形貌进行了研究,反应终止是铝粒表面的变质层引起的,通过强力搅拌和稀盐酸的清洗可以改善铝粒表面,除去变质层,反应是可以连续进行的。 运用星形球磨机对前驱体进行湿磨,研究了球磨参数对前驱体的影响,最后在250r/min转速下球磨4小时后得到了高纯的氢氧化铝,将高纯氢氧化铝在1200℃×2h制度下煅烧得到了α-Al2O3,用ICP-OES检测其纯度达到99.9932%,经超声波处理8min后检测其粒度为16.54μm。
[Abstract]:In this paper, the preparation of high purity ultrafine alumina by electrical discharge method is studied systematically. The high purity ultrafine alumina is prepared by using a very safe low voltage DC power supply for discharge experiments, and the following conclusions are drawn:. The precursor of Al(OH)3 and Al was prepared by spark discharge in secondary deionized water with different purity of metal aluminum. The impurities outside of them mainly depend on the purity of raw material aluminum, and the spark discharge process will not cause new pollution. The mechanism of spark discharge is studied. It is found that the content of residual aluminum mainly depends on the amount of electrical corrosion of discontinuous discharge, and the amount of electric corrosion of discontinuous discharge depends on the energy of discontinuous discharge, and the magnitude of energy of discontinuous discharge depends on voltage and current. Pulse width and other factors. The surface morphology of aluminum particles after discharge is studied. The reaction termination is caused by the metamorphic layer on the surface of aluminum particles. The surface of aluminum particles can be improved by strong stirring and cleaning with dilute hydrochloric acid, and the metamorphic layer can be removed. The reaction can be carried out continuously. The influence of ball milling parameters on the precursor was studied by wet milling with a star ball mill. At last, high purity aluminum hydroxide was obtained after 4 hours of milling at 250 r / min rotational speed. 伪 -Al _ 2O _ 3 was obtained by calcination of high-purity aluminum hydroxide at 1200 鈩，

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