CAO Feng1, LONG Shigang1, WU Xingrong1, SUN Jialin2, HONG Yanruo2
Abstract
The aim of this experimental work was to investigate the rheological and adhesive performance of gunning refractory suspensions. The results of rheological tests indicate that: the rheological curve of gunning refractory bonded by high-alumina cement(HACG) is Bingham type; the rheological curve of low cement gunning refractory(LCG) bonded by microsilica is characterized by pseudo-plasticity fluid with yielding stress; and the rheological property of low-cement gunning refractory bonded by microsilica is proved to be better than that of gunning refractory bonded by cement. Meanwhile as indicated by the adhesive tests: the better the rheological properties of gunning refractory suspension, the better the repair effect has. 
Key words: Rheological property, Gunning refractory, Suspension, Viscosity, Refractory, Blast furnace
 

CHEN Zhiqiang Bjørn Myhre and Bjørn Sandberg
Abstract
Installation of refractory castables depend not only on flow, but also on how soon the flow is lost because of setting. The loss of flow (flow decay) has always been one of the main problems of refractory castable manufacturers, a problem that has not been too well described in literature. The flow decay has been studied for a castable system based on alumina, pointing out some general trends. The flow decay was found very temperature sensitive, being strongly accelerated by temperature increases. To compensate for excessive flow loss, a retarder like citric acid may be used. Thus flow decay was measured as a function of citric acid (retarder) addition at 35°C. 
Key words: Refractory, Flow, Flow decay, Alumina based castable, Retarder, Setting time

LI HONGXIA YANG BIN YANG JINSHONG LIU GUOQI
Abstract
TSCC (Thin Slab Continuous Casting) as a high performance continuous casting technology is now quickly developed in China. Since the first TSCC caster went into operation in 1999 in Guangzhou Zhujiang Iron & Steel Ltd., 5 casters of TSCC have been put into production in China, and another five TSCC production lines are in constructing. The SEN (Submerged Entry Nozzle) for TSCC take a more important role in the operation of caster than the SEN for common slab continuous casting, which determine the sequence casting time, influence the quality of the slab and the benefit of the caster. The SEN for TSCC also should have more excellent properties to satisfy the more severe application conditions and higher requirement of continuous casting time. According the practice the failure causes of SEN in application is mainly over-corrosion of slag line of the SEN. ZG (Zirconia-Graphite) materials are commonly widely applied to the slag line, owing to its higher corrosion resistance to liquid slag than other materials. Many authors have studied the corrosion resistance of ZG materials 1-4). It is generally accepted that the attack process of SEN powder line is a cyclic mechanisms-ZrO2 dissolved by molten flux and graphite dissolved into molten steel, among them zirconia dissolution via destabilization in the corrosion process is the rate-controlling step. In order to enhance the casting charges of the SEN, some efforts have been reported, such as increasing ZrO2 content, optimum particle size distribution of ZrO2 and using anti-oxidation additions, etc5-7) In this study, different anti-oxidation additions and fused ZrO2 raw materials with different microstructure were tested to compare the influence of these materials to corrosion resistance.
 

Molin1, K. Ghanbari Ahari2, B. Josiek1 and J. Molin3
Abstract
Physical properties and microstructural evolution on firing of 3 types of bauxite based refractory bricks were carried out using techniques such as porosimetry, XRD and SEM. The groups differed from each other by progressive refining of the matrix or bond phase. It is revealed that such a refinement of the matrix can improve the high temperature properties of the bricks made from poor grade materials. 
Key words: Bauxite based bricks, Refinement of matrix, Physical properties
 

ZHANG Xiuqin, ZHI Xiaoming and WANG Hongmei
Abstract
In order to meet the needs of hot repairing technology of coke oven, the zero expansion silica brick with super properties has been developed, and the problem of poor thermal stability of common silica brick has been overcome. This product can be directly used after being rapidly heated after construction. At present, it has been applied in coke ovens in Italy and Baosteel. 
Key words: Silica bricks, Low expansion, Hot repairing, Coke oven
 

Zhao Huizhong1,2 Hu Shoutian1 Wang Houzhi1,2 Zhang wenjie2
Abstract
Nanoscale mullite powder were synthesized via Sol-gel-SCFD and middle temperature treatment by using AIP (aluminum-isopropoxde) and TEOS (tetraethyl orthosilicate) as starting materials, Both of the binary aerogel of alumina-silica and calcined nanoscale materials were investigated by using TG-DSC (thermogravimetry- differential scanning calorimeter), TEM(transmission electron microscope), XRD(X-Ray diffractometer ) and specific surface area and porosimetry. TG-DSC indicated the removal of most of the volatiles, i.e. 15.98% up to about 7000C, and in the DSC curve, existence two exothermic peak at about 4450C and 10150C may be due to the crystallization of Si-O-Al-O in diphasic gels and mullitization and a small endothermic peak at about 8050C indicated the decomposition of structural water molecules. Colligation the results of TG-DSC, XRD and TEM, the beginning temperature of mullitization in Al2O3-SiO2 aerogel system can be confirmed at about 10150C. XRD results also showed the formation of mullite at the range 1100~12000C. TEM and surface area and porosimetry results showed that the nanosized mullite were calcinated at 1100 and 12000C exhibited size 30nm and 50nm, specific surface area 138.91m2/g and 95.81m2/g. Keywords: Nanosized mullite, Sol-Gel, Supercritical fluid drying，synthesis, calcinations