利用NH4Cl其分解时释放气体的特点控制以碳酸铝铵为前驱体的氧化铝α相变过程中的团聚。采用DTA、XRD、SEM和粒度分析等手段研究了在升温过程中其对氧化铝α相变过程及产物的影响。结果表明,由于NH4Cl在分解时释放气体所产生的冲击作用,相变过程中团聚受到削弱,相变产物的粒径和晶粒尺寸都有所减小。但是氧化铝α相变温度并未有明显下降。
Effect of NH4Cl on phase transformation of Al2O3 obtained from ammonium aluminum carbonate hydroxide (AACH) has been studied. It is found that NH4Cl could lower packing density of transitional Al2O3 by decomposed gases. Therefore hard aggregate was retarded in α phase transformation process. Fine α-Al2O3 powders were obtained. However, the resulting α-Al2O3 exhibited more dendritic morphology.