纳米级氧化铝及掺钡氧化铝的物相转变

Phase Transition of Nanoscale Pure and Ba^(2+) Doped Alumina

采用直接沉淀法后低温煅烧获得纳米级氧化铝,采用蒸发溶剂法直接掺入Ba2+获得掺杂氧化铝,分别高温煅烧后获得煅烧样品,并对样品进行热分析、X射线衍射测试和透射电镜观察。结果表明,纳米级氧化铝及其掺杂Ba2+后随温度升高时的物相转变顺序为γ-Al2O3—δ-Al2O3—θ-Al2O3—α-Al2O3,各相转变发生时的温度范围为100~200℃;Ba2+的引入不改变转变顺序,但提高了各转变所需的温度。

Nanoscale alumina powders were prepared by low temperature calcining after direct precipitation.With directly incorporating Ba2+,the doped alumina was compounded through solvent evaporation method.The calcined samples were obtained by calcining the two kinds of samples at high temperature respectively.The samples were tested by thermal analyzer,XRD and TEM.The results show that the phase transformation order of nanometer alumina and Ba2+dopped with temperature increasing is γ-Al2O3—δ-Al2O3—θ-Al2O3—α-Al2O3.The temperature ranges at transition stage are obtained.The doping of Ba2+ does not change the transformation order,but can improve the transformation temperature.