α-Al_2O_3含量对刚玉-莫来石材料物理性能的影响

Effects of α-Al_2O_3 Content on Physical Properties of Corundum-mullite Materials

以电熔莫来石、板状刚玉为骨料,加入不同量α-Al2O3细粉,在1600℃保温3 h烧成。检测了试样的体积密度、显气孔率、抗折强度、抗热震性,并结合X射线衍射(XRD)、扫描电子显微镜(SEM)和EDAX分析了试样的显微结构。结果表明,试样在经过1600℃烧成后,随着α-Al2O3微粉含量的提高,试样体积密度和高温抗折强度呈先升高后降低的趋势,耐压强度逐渐降低;α-Al2O3微粉含量为8%的刚玉-莫来石材料,经1600℃烧成后α-Al2O3颗粒长大,分布均匀,结合紧密,形成连续的交错网络骨架结构,具有较好的物理性能。

The corundum-mullite materials were fabricated using fused mullite and tabular corundum as raw materials,and effect of the content of α-Al2O3 powder（6%,8%,10%,12%）on its properties such as bulk density,apparent porosity,bending strength,and thermal shock resistance have been studied.The microstructure of the samples has been investigated by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and energy dispersive spectrometer（EDAX）.The results show that both the bulk density and high temperature strength of samples sintered at 1600 ℃ for 3 h are first increasing and then decreasing with the increase of α-Al2O3 content.When the content of α-Al2O3 is about 8%,the particle grows up and bonds closely.So the network has been formed and give rise to corundum-mullite materials with better physical properties.