Unburned magnesium aluminate spinel refractories were prepared using sintered magnesium aluminate spinel as the main raw material,phenolic resin as the binder,aluminum powder(2%,4%,and 6%by mass)and silicon powder(whe...Unburned magnesium aluminate spinel refractories were prepared using sintered magnesium aluminate spinel as the main raw material,phenolic resin as the binder,aluminum powder(2%,4%,and 6%by mass)and silicon powder(when Al powder addition is 4%,Si powder addition varies:1%and 2%,by mass)as additives.The effects of the Al powder and Si powder additions on the properties and microstructure of the refractories heat treated at different temperatures(1000,1400,and 1600℃for 3 h)were studied.The results show that the Al powder addition can greatly enhance the cold modulus of rupture of the samples fired at 1000 or 1400℃,and meanwhile AlN reinforcement phase forms in the matrix,which greatly improves the hot modulus of rupture of the samples at 1400℃;however,the heat treatment at 1600℃has little influence on the strength;the addition of Al powder and Si powder results in the formation of low melting point phases,greatly reducing the hot modulus of rupture.However,the low melting point phases promote sintering,which enhances the density and the cold modulus of rupture,and decreases the volume change during heating.The samples added with Al and Si all have higher cold modulus of rupture than those added with Al powder only.展开更多
To extend the service life of the upper checker bricks in the regenerator of glass furnaces with petroleum coke as fuel,the corrosion resistance of magnesia-chrome and alumina-chrome bricks with the similar apparent p...To extend the service life of the upper checker bricks in the regenerator of glass furnaces with petroleum coke as fuel,the corrosion resistance of magnesia-chrome and alumina-chrome bricks with the similar apparent porosity was systematically researched.The results show that the Cr2O3 content and the microstructure present significant effects on the corrosion resistance.The molten corrosion reagent forms silicate and vanadate phases with low melting points between MgO crystals in magnesia-chrome bricks,and the volume strain generated by the melting and solidification process leads to the cracking and spalling of refractories,which intensifies the corrosion process.The encapsulation of alumina particles by alumina-chrome solid solutions in alumina-chrome bricks avoids contact with the low melting point liquid phases and improves the corrosion resistance of refractories.展开更多
Structure, crystallization and dissolution properties of CaO-MgO-SiO2 inorganic glass fiber in the presence of additives (Al2O3, Y2O3) were investigated by DTA, XRD, FTIR and ICP-AES techniques. The results show that ...Structure, crystallization and dissolution properties of CaO-MgO-SiO2 inorganic glass fiber in the presence of additives (Al2O3, Y2O3) were investigated by DTA, XRD, FTIR and ICP-AES techniques. The results show that with the addition of Al2O3 and Y2O3, the glass network structure is strengthened and the precipitation of crystals is inhibited for heat-treated fibers. Compared with Y2O3 doped fibers, Al2O3 presents more significant effects on the enhancement of silica network and the inhibition of crystallization in fibers. As for dissolution properties in physiological fluids, though the weight losses, changes of pH values and leached ions concentration lower slightly with the addition of Al2O3 and Y2O3 for the intensified network structure, and fibers still present high dissolution rates.展开更多
耐火材料是高温工业重要的支撑材料,随着相关技术的不断发展,已经积累了海量的文献。然而使用传统方法阅读如此众多的文献存在较大的困难,进一步对其进行分析归纳则难度更大,因而以往的做法常是凭借经验选择代表性文献进行总结分析。但...耐火材料是高温工业重要的支撑材料,随着相关技术的不断发展,已经积累了海量的文献。然而使用传统方法阅读如此众多的文献存在较大的困难,进一步对其进行分析归纳则难度更大,因而以往的做法常是凭借经验选择代表性文献进行总结分析。但该方法难以对研究动态有全面、定量、深入的分析与归纳,不利于系统地把握发展现状及趋势,已经逐渐难以适应科学研究的未来需要。本工作从知识图谱视角对耐火材料研究的现状进行归纳和总结,对中国知网和WOS(Web of Science)核心数据库中的众多文献进行分析,分别从中国和世界范围介绍了耐火材料领域研究的整体发展脉络,并以含碳耐火材料为例介绍了领域内的研究热点与趋势,最后对耐火材料及知识图谱的未来发展作出了展望。展开更多
文摘Unburned magnesium aluminate spinel refractories were prepared using sintered magnesium aluminate spinel as the main raw material,phenolic resin as the binder,aluminum powder(2%,4%,and 6%by mass)and silicon powder(when Al powder addition is 4%,Si powder addition varies:1%and 2%,by mass)as additives.The effects of the Al powder and Si powder additions on the properties and microstructure of the refractories heat treated at different temperatures(1000,1400,and 1600℃for 3 h)were studied.The results show that the Al powder addition can greatly enhance the cold modulus of rupture of the samples fired at 1000 or 1400℃,and meanwhile AlN reinforcement phase forms in the matrix,which greatly improves the hot modulus of rupture of the samples at 1400℃;however,the heat treatment at 1600℃has little influence on the strength;the addition of Al powder and Si powder results in the formation of low melting point phases,greatly reducing the hot modulus of rupture.However,the low melting point phases promote sintering,which enhances the density and the cold modulus of rupture,and decreases the volume change during heating.The samples added with Al and Si all have higher cold modulus of rupture than those added with Al powder only.
基金support from the National Natural Science Foundation of China(U20A20239)the Key Research and Development Project of Hubei Province,China(2022BAA032).
文摘To extend the service life of the upper checker bricks in the regenerator of glass furnaces with petroleum coke as fuel,the corrosion resistance of magnesia-chrome and alumina-chrome bricks with the similar apparent porosity was systematically researched.The results show that the Cr2O3 content and the microstructure present significant effects on the corrosion resistance.The molten corrosion reagent forms silicate and vanadate phases with low melting points between MgO crystals in magnesia-chrome bricks,and the volume strain generated by the melting and solidification process leads to the cracking and spalling of refractories,which intensifies the corrosion process.The encapsulation of alumina particles by alumina-chrome solid solutions in alumina-chrome bricks avoids contact with the low melting point liquid phases and improves the corrosion resistance of refractories.
基金the National High Technology Research and Development Program ("863" Program) of China (No.2009AA032503)the National Natural Science Foundation of China (Nos.50872098, 51004080)the Open Fund of the Key State Laboratory Breeding Base of Refractories and Ceramics (Wuhan University of Science and Technology (No.G201004)
文摘Structure, crystallization and dissolution properties of CaO-MgO-SiO2 inorganic glass fiber in the presence of additives (Al2O3, Y2O3) were investigated by DTA, XRD, FTIR and ICP-AES techniques. The results show that with the addition of Al2O3 and Y2O3, the glass network structure is strengthened and the precipitation of crystals is inhibited for heat-treated fibers. Compared with Y2O3 doped fibers, Al2O3 presents more significant effects on the enhancement of silica network and the inhibition of crystallization in fibers. As for dissolution properties in physiological fluids, though the weight losses, changes of pH values and leached ions concentration lower slightly with the addition of Al2O3 and Y2O3 for the intensified network structure, and fibers still present high dissolution rates.
文摘耐火材料是高温工业重要的支撑材料,随着相关技术的不断发展,已经积累了海量的文献。然而使用传统方法阅读如此众多的文献存在较大的困难,进一步对其进行分析归纳则难度更大,因而以往的做法常是凭借经验选择代表性文献进行总结分析。但该方法难以对研究动态有全面、定量、深入的分析与归纳,不利于系统地把握发展现状及趋势,已经逐渐难以适应科学研究的未来需要。本工作从知识图谱视角对耐火材料研究的现状进行归纳和总结,对中国知网和WOS(Web of Science)核心数据库中的众多文献进行分析,分别从中国和世界范围介绍了耐火材料领域研究的整体发展脉络,并以含碳耐火材料为例介绍了领域内的研究热点与趋势,最后对耐火材料及知识图谱的未来发展作出了展望。
