(1.華東理工大學(xué) 超細(xì)粉末國(guó)家工程研究中心,
上海 200237；
2.江蘇大學(xué) 材料科學(xué)與工程學(xué)院， 鎮(zhèn)江 212013)
摘 要: 將超聲輻射應(yīng)用于以硫酸鋁銨（NH4Al(SO4)2·12H2O ）和碳酸氫銨（NH4HCO3）為原料的沉淀法制備Al2O3納米粉體的化學(xué)反應(yīng)工藝過(guò)程， 制備了粒徑為12nm的α-Al2O3納米粉體。 通過(guò)SEM、 TEM等分析手段研究了超聲輻射對(duì)前驅(qū)體NH4Al(OH)2CO3沉淀物及最終粉體尺寸、 形貌及其團(tuán)聚行為的影響，并探討了其作用機(jī)理。 結(jié)果表明： 超聲輻射由于其自身的空化作用不僅細(xì)化了前驅(qū)體顆粒、 抑制了其間的團(tuán)聚， 而且延緩了其向凝膠的轉(zhuǎn)變過(guò)程， 從而有效地細(xì)化α-Al2O3顆粒，但過(guò)高的頻率卻易導(dǎo)致顆粒間的進(jìn)一步聚合。
關(guān)鍵字: 超聲波； 沉淀； 納米Al2O3
（1. National Engineering Research Center of Ultrafine Powder,
East China University of Science and Technology, Shanghai 200237, China;
2. School of Materials Science and Engineering, Jiangsu University,
Zhenjiang 212013, China）
Abstract:The α-Al2O3 particle with an average diameter of 12nm was prepared by precipitation method under ultrasonic radiation using NH4Al(SO4)2·12H2O and NH4HCO3 as raw materials. The effects of ultrasonic radiation on the size and appearance of precursor and Al2O3 particle were investigated by means of SEM and TEM, the mechanism was also studied. The results show that because of the cavitate ultrasonic radiation can not only make the precursor smaller and reduce its agglomeration, but also slow down the speed of change to gel. Ultrasonic radiation can refine α-Al2O3 nanoparticle effectively, but too high ultrasonic frequency will cause further agglomeration between particles.
Key words: ultrasonic; precipitation; Al2O3 nanopowder
