以活性氧化铝为原料,分别引入La2O3、LaAlO3和预合成的LaAl11O18,制备刚玉-六铝酸镧复相材料.研究了氧化镧的不同引入方式、引入量和煅烧温度对刚玉-六铝酸镧复相材料的烧结行为的影响,并通过XRD、SEM等手段对其物相组成和显微结构进行表征.结果表明:在活性氧化铝中加入La2O3,LaAlO3和预合成LaAl11O18,均能生成六铝酸镧相,生成的六铝酸镧分布在刚玉晶粒的晶界处,不利于刚玉陶瓷的烧结,以LaAlO3为氧化镧源制备的试样致密化程度高;随着LaAlO3含量的增加试样致密化程度逐渐减小,当煅烧温度为1650 ℃时,试样的致密化程度相对较高,刚玉和六铝酸镧晶粒尺寸相对较小.%Al2O3-LaAl11O18composites were prepared by the activated alumina as raw material, respectively, La2O3, LaAlO3and pre-synthesized LaAl11O18for different source of lanthanum. The effects of different sources of lanthanum, content and sintering temperatures on the properties of Al2O3-LaAl11O18composites were investigated. The phase composition and microstructure of the samples were characterized by XRD and SEM. The results showed that the addition of La2O3, LaAlO3and pre-synthesized LaAl11O18in the activated alumina could form LaAl11O18phase. The lanthanum hexa-aluminate grains are distributed along the grain boundary of corundum grains, which is not conducive to the sintering of corundum ceramics. The density of samples with LaAlO3as source of lanthanum is higher than others. With the increase of LaAlO3content, the degree of densification decreases .When the calcination temperature is 1650 ℃, the densification degree of the sample is higher, and the grain size of corundum and lanthanum hexaaluminate is relatively small.
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