摘要
采用K2CO3浸渗碳粉、石墨覆盖合金熔体液面,预设多孔陶瓷体输通空气,实现了铝合金熔体由表面向其内部推进的原位自氧化反应。反应生成物致密,周边宏观表面平整,生长体前沿无高低不平的胞状堆积现象。经显微组织观察、微区波谱成分分析及X射线衍射结构分析发现:反应生成物是以柱状晶团形式生长,而柱状晶则由微米级的块、粒状氧化物构成。氧化物的组成以Al2O3为主,含少量SiO2,在两相及块、粒之间成分呈连续过渡变化,无明显清晰的分界,且有以Al2O3包覆SiO2生长的倾向,并表现出很强的定向性。铝合金金属相则主要分布于柱状晶团交界处。
A novel technique by using graphite immersed by K2CO3 solution to cover with the surface of molten alloy and setting porous ceramics in advance to transport atmosphere, is realized to in situ oxygenize molten alloy from its surface into its interior. The attractive features of the new technology in comparison with conventional growth technology are densified reaction resultant, smooth macro-surface around samples, and samples of front without rugged cellular stacking on them. It is found by microstructure observation, X-radial diffraction analysis (XRD) and by electron probe X-ray microanalysis (EPMA) that oxides grow in the form of columnar crystal consisting of clumps or grains of micron oxides in which α-alumina is the main and silica a little, with continuous ingredient variation between two phases and clumps or grains, showing a tendency of α-alumina wrapping silica without distinct surfaces between them, and having the strong character of directional growth: and alloy phases mainly distribute in the interface of columnar crystal corps.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2004年第2期34-39,共6页
Acta Materiae Compositae Sinica
基金
陕西省教育厅科技创新基金项目(03JK139)
关键词
熔体氧化生长
复合材料
模糊界面
原位反应生长
包覆
Composite materials
Crystal growth from melt
In situ processing
Microstructure
Oxidation
