机构地区: 中钢集团洛阳耐火材料研究院有限公司
出 处: 《耐火材料》 2009年第6期433-437,共5页
摘 要: 釆用光学显微镜、扫描电子显微镜、能谱仪、波谱仪和X射线衍射仪研究了熔铸α,β-Al2O3制品的显微结构,取自铸块表面向内100 mm厚度的样品分4段检验,表征了晶体形貌特征。结果发现:由于不同段带冷却速率的差异,致使主晶相α-Al2O3和β-Al2O3的结晶形态呈现变异,显微结构明显不同,并且α-Al2O3和β-Al2O3在不同段带内的含量也不尽相同,由表面往里α-Al2O3的含量依次增加;以波谱仪测定了各段带β-Al2O3的组成,基本上属于n(Na2O):n(Al2O3)=1:(11~12)型的β-Al2O3组成范围;初晶相刚玉呈现包晶反应的典型形貌,而β-Al2O3结晶达毫米级柱状晶体,解理十分完全,解理面平直,间距为50~100μm;α-Al2O3和β-Al2O3晶体之间有一定量的气孔和结合相,结合相为霞石固溶体,其体积分数为2%~3%。 The microstructure of a fused cast α,β-Al2O3 block manufactured by a classic recipe and production process was studied by means of optical microscope (OM), scanning electron microscope ( SEM), ener- gy dispersion spectroscope (EDS) ,wave dispersion spectroscope (WDS) and X-ray diffraction (XRD). Its crystal morphology was paid special attention to 4 sections taken from the surface of this block into linear 100 mm thickness. It is found that α- Al2O3 and β-Al2O3 in different sections have different crystal shapes and microstructures because of their different cooling rates. The contents of α- Al2O3 and β-Al2O3 are not the same in the different sections and the content of α- Al2O3 increases from the surface to inside. The WDS analysis shows that the mole ratio of Na20 and Al2O3 in β-Al2O3 is essentially 1 :( 11 -12) in different sec- tions. Typical morphology of peritectic reaction is found in the primary phase of corundum. And β-Al2O3 crystals are the columnar crystal with sizes in millimeters and cleavage is complete whose plane is straight. The space distance between two cleavages is 50 - 100 μm.α-Al2O3 and β-Al2O3crystals are combined with some pores and about 2vol% -3vol% nepheline solid solution bonded phase.