USE OF ALUMINUM METAL IN THE CERAMIC INDUSTRY: II,EFFECT OF COATING INSULATING FIREBRICK WITH ALUMINUM-FIRE-CLAY MIXTURES*

After insulating firebrick are reheated in service, many of them contract too much and develop large open shrinkage cracks. By first applying to the surfaces a 0.035-in. coating composed of aluminum and fire clay, these brick usually remain intact and constant in size when they are reheated. The coating also becomes hard, causing the brick to become more resistant to abrasion, slag action, permeability of gases, load at high temperatures, and sudden temperature changes. Coatings composed of 60 to 70% of fire clay and 30 to 40% of aluminum powder were found to overcome most of these deficiencies in insulating firebrick.     

USE OF CAST ALUMINA REFRACTORIES IN THE GLASS INDUSTRY *

The development of cast alumina refractories is briefly described, and the physical and chemical properties of three types of high-alumina, fusion-cast refractories that have proved commercially successful are given. Such properties as microstructure and glass-refractory interface reactions are discussed, and the use of these refractories with several different types of glass is described.     

THE USE OF PLASTIC CLAY GROG IN PREVENTING SPALLING1

Effect of calcined clay grog on the properties of fire-brick .—A medium dense-burning clay was calcined at cone 8, then ground and mixed with plastic clay in various proportions up to 40 per cent. An air spalling test of the burned bricks showed that the grog increased the resistance to spalling about 5 per cent for each per cent of grog added. The results for other physical properties agreed with those found by previous observers; the bricks with grog were more porous and weaker mechanically but showed less drying and burning shrinkage.     

REFRACTORIES FOR USE IN SULPHATE-RECOVERY FURNACES OF THE PULP AND PAPER INDUSTRIES*

The paper gives a short review of the soda-recovery methods used in the Kraft process. The tests made to determine the relative merits of different refractories were (1) P.C.E. determinations of soda-refractory mixtures, (2) simulative-service slag tests, and (3) petrographic analyses. Tests indicate that resistance is produced by (1) an impervious crystalline structure, such as soapstone for the low temperatures and electro-cast mullite for the high temperatures, or (2) chemical inertness in contact with soda, such as is found with purer forms of magnesia.     

THE IMPORTANCE OF ACCURATE SAMPLING IN THE PRODUCTION AND USE OF CERAMIC MATERIALS*

A discussion of the theory and methods of sampling and their application to the production and use of feldspar and other ceramic materials is presented. Analytical data concerning segregation within shipments and bin contents arc given.     

A STUDY OF THE FACTORS INVOLVED IN THE SPALLING OF FIRE CLAY REFRACTORIES WITH SOME NOTES ON THE LOAD AND REHEATING TESTS AND THE EFFECT OF GRIND ON SHRINKAGE1

Of the three factors, elasticity, coefficient of expansion and rate of temperature change, which affect spalling, the former is by far the most important. Only small differences are found between fire clay mixtures of widely varying structure and composition in the rate at which they change in temperature under like conditions of heating. The coefficient of expansion varies directly with the silica content and differences in this respect of large order were found. However, the spalling on the particular mixtures tested varied almost inversely as the coefficient of expansion. This apparent discrepancy is explained on the basis of greater elastic properties of the brick which had high expansions. The elasticity may be varied between wide limits and is sufficiently important as to overbalance the effect of greater expansion. This property is accordingly the one upon which efforts directed toward the development of non-spalling brick should be centered. It was discovered that a plastic deformation could be obtained at as low a temperature as 635°C. This gives the effect of elasticity and undoubtedly has considerable influence on spalling at the higher temperature ranges. Results are given for a number of load tests which show clearly the importance of hard firing. The secondary expansion of brick made from Pennsylvania flint clay is shown to be influenced by the temperature of reheating, as well as its rate. Detailed results showing the effect of grind and firing on the finished size of the brick included in the investigation are also given.     

EFFECT OF MIGRATION OF CLAY MINERALS AND HYDROUS ALUMINUM OXIDES ON THE COMPLEXITY OF CLAY*

Movement of montmorillonite, nontronite, kaolinite, halloysite, dickite, gibbsite, and diaspore within clays after they were first formed is indicated by the relations reported in this paper. Migration of these minerals takes place rarely by transfer of their constituents as true solutions but generally as colloidal suspensions whose formation and movement are favored by conditions of good drainage and the presence of dispersing agents. This migration increases the complexity of the clays affected by it and accounts for some of the variations in the composition of a single body of clay met by the clay producer.     

THE USE OF TRIBARIUM GUMINATE IN STRUCTURAL CLAY PRODUCTS*

Tribarium aluminate was used in brick and sewer pipe, both on laboratory and plant scale tests. It was found to be efficient both as a scum preventive and as a producer of better density and color.     

THE EFFECT OF MECHANICAL PRESSURE ON THE IMBIBITIONAL AND DRYING PROPERTIES OF SOME CERAMIC CLAYS,I*

A number of ceramic clays in the plastic condition were held between water-permeable pistons under mechanical pressure of from 200 to 20,000 pounds per square inch in contact with water at atmospheric pressure until equilibrium was reached; the water in the pistons was removed by compressed air, the pressure released. and the moisture content, density, drying shrinkage, and other properties of the clays determined. In every case, the moisture content and drying shrinkage decreased with increasing pressure and with some clays at high pressures expansion occurred on drying. Rather complete data are given for a number of clays and their theoretical and practical significance is discussed.     

从《白土案》看陶冶对小环境的影响

《白土案》述及南康府星子县因开挖白土而引起的环境变迁。开挖白土仅仅是陶冶的一个步骤,就引起了人与环境关系的恶化,正是这种恶化酿成此案的发生,造成了对当地环境的三大威胁:危及田园,危及庐墓,危及地脉风水。南康府最终决定封山禁开,以保护环境。本文基于文献资料上分析了此案所涉及的陶冶对小环境的这三个威胁。     

论陶瓷碎片在地面铺装设计中的运用

由于工业化大生产与千百年的历史遗存,我国有大量陶瓷碎片,这里以其为研究对象,着重探讨陶瓷碎片在室内设计与景观设计地面铺装中的运用,并指出其运用原则,为陶瓷碎片的再利用拓展途径。     

SOME FACTORS INFLUENCING THE THERMAL PROPERTIES OF MINERALS AND PRODUCTS OF THE CERAMIC INDUSTRY1

A survey is given of a number of factors which exert an influence upon the following thermal properties of several minerals and ceramic bodies: specific heat, thermal reaction, thermal conductivity, thermal expansion, thermal radiation, etc. The influences in the Case of fired and unfired substances are differentiated. A bibliography is presented, which summarizes the work of recent years bearing on the thermal properties of minerals and ceramic bodies.     

THE USE OF SILICON-CARBIDE REFRACTORIES IN BOILER FURNACES1

The chief causes of failure of refractories in boiler furnaces are slag adhesion, erosion, and failure of structure, dependent on the type of coals and feeds used. Some of the physical and chemical properties of different types of refractories are given. The development of bonded silicon carbide brick is mentioned. Clinker trouble is eliminated by use of these brick in furnaces using all kinds of present day stoker equipment. Failures due to chemical reaction between iron and silicon carbide, and torch action on a wall produced by a blast of flame under pressure together with medium amounts of iron in the ash are discussed. Air cooling of walls is taken up. Installations of air-cooled silicon-carbide blocks are listed and discussed. Water cooling, the use of preheated air, and conditions of use of the water wall are taken up.     

悬浮体中团聚体的产生机理及其对材料结构与性能的影响

研究了陶瓷胶态成型过程悬浮体中产生团聚体的微观机理,根据液体介质中陶瓷粉体颗粒之间的作用势,建立了团聚体产生的微观结构模型.利用环境扫描电子显微镜对悬浮体中粉体团聚的显微结构进行"准"直接观察,发现悬浮体中存在2种团聚体形态:Ⅰ型团聚体(硬团聚)和Ⅱ型团聚体(软团聚),揭示了团聚体的产生是由于浆料的固相含量偏离了稳定固相含量.研究发现:悬浮体中的团聚体会遗传到陶瓷体中,并对陶瓷构件的力学性能有显著影响.探讨了团聚体对烧结体的结构及力学性能影响的原因.当悬浮体中固相含量低于稳定固相体积分数ψ0时,悬浮体中会形成松散团聚即软团聚;当固相含量超过ψ0时,悬浮体中会形成紧密团聚即硬团聚:当固相含量等于ψ0时,悬浮体具有均匀分散的稳定结构.由于悬浮体固相含量偏离稳定周相含量ψ0而在悬浮体中产生的团聚体,会由于原位周化而遗传到坯体之中,影响烧结体结构的均匀性.     

论规模与结构在景德镇陶瓷产业中的地位

大中型陶瓷企业与小型陶瓷企业有着各自的特长,能适应陶瓷产品中不同特性生产需要。振兴景德镇陶瓷经济产业,就应将大中型陶瓷企业与小型陶瓷企业结合起来,去满足陶瓷经济中各种陶瓷产品生产的需要。     

中国陶瓷产业的现代化进程与陶瓷装备

中国国际陶瓷工业展览会办到2008年这一届,有22届了.曾亲身经历目睹过22届的人或是从中参加或参观过几届的人,都会有一个共识:将历届的陶瓷展活动串联起来,就是中国陶瓷业从传统走向现代进程的真实写照,就是国家实行改革开放政策30年以来中国陶瓷业的发展史.     

人工神经网络技术及其在陶瓷工业中的应用

本文分析了人工神经网络技术的发展及特点,结合其在陶瓷工业中的应用情况,包括窑炉温度场分布的预测、窑炉烧趸的工况辨识、ＰＴＣ材料性能识别、陶瓷缺陷的分析及耐火材料ＳｉＣ生产量的拟万预报等,阐述了人工神经网络技术在陶瓷工业有广阔的应用前景。     

DETERMINING THE EFFECTS OF THE RATE OF FIRING AND RAPID AND SLOW COOLING ON THE PHYSICAL PROPERTIES OF FIRECLAY REFRACTORIES*

This investigation determined that the rate of firing, as specified in the standard test for the firing behavior of fireclay refractories, could be reduced without materially affecting the accuracy of the data obtained. The rate of cooling is found to be the cause of variations between test results and laboratory and factory results.     

THERMODYNAMIC PROPERTIES OF BINARY LIQUID MIXTURES OF ETHANE AND ETHYLENE WITH METHANE AND THE RARE GASES

Two series of binary liquid mixtures containing either ethylene or ethane have been investigated, at one or more temperatures (usually at the triple-point temperature of the component with the higher melting-point). In the ethylene series liquid-vapour equilibrium and liquid density studies were carried out for mixtures with methane, krypton and xenon; the heats of mixing were also measured for the ethylene + krypton mixtures. In the ethane series, which comprised mixtures with methane, argon, krypton and xenon, all three properties were measured except for the ethane + methane and ethane + argon systems where the enthalpies of mixing were already known. The ethylene + ethane system was also investigated at 161.39 K.

The results have been used to estimate the thermodynamic excess functions G^E , V^E and H^E . The G^E values decrease, within each series, as one moves from the lighter to the heavier rare gas, the values being lower in the ethane series. For the ethane + xenon mixtures both G^E and H^E are negative, showing a weak attraction between the two molecules. The V^E values for the mixtures of hydrocarbons suggest the probable formation of interlocking structures between the two components.

The values of the thermodynamic excess functions have been interpreted in the light of the model of Frisch-Longuet Higgins-Widom for the liquid state.     

THERMODYNAMIC PROPERTIES OF BINARY LIQUID MIXTURES OF ETHANE AND ETHYLENE WITH METHANE AND THE RARE GASES

Two series of binary liquid mixtures containing either ethylene or ethane have been investigated, at one or more temperatures (usually at the triple-point temperature of the component with the higher melting-point). In the ethylene series liquid-vapour equilibrium and liquid density studies were carried out for mixtures with methane, krypton and xenon; the heats of mixing were also measured for the ethylene + krypton mixtures. In the ethane series, which comprised mixtures with methane, argon, krypton and xenon, all three properties were measured except for the ethane + methane and ethane + argon systems where the enthalpies of mixing were already known. The ethylene + ethane system was also investigated at 161.39 K.

The results have been used to estimate the thermodynamic excess functions G^E, V^E and H^E. The G^E values decrease, within each series, as one moves from the lighter to the heavier rare gas, the values being lower in the ethane series. For the ethane + xenon mixtures both G^E and H^E are negative, showing a weak attraction between the two molecules. The V^E values for the mixtures of hydrocarbons suggest the probable formation of interlocking structures between the two components.

The values of the thermodynamic excess functions have been interpreted in the light of the model of Frisch-Longuet Higgins-Widom for the liquid state.