熔铸α,β-Al_2O_3制品的包晶显微结构  

Peritectic microstructure of fused cast α,β-alumina block

作　　者：高振昕[1] 张伟[1] 黄振武[1] 卫晓辉[1] 任刚伟[1] 常亮[1] 

机构地区：[1]中钢集团洛阳耐火材料研究院有限公司,河南洛阳471039

出　　处：《耐火材料》2009年第6期433-437,共5页Refractories

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.

关 键 词：熔铸α β 氧化铝制品 包晶 晶体形貌 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业] TG111.4[金属学及工艺—物理冶金]