共查询到18条相似文献,搜索用时 15 毫秒
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以板状刚玉为主要原料,纯铝酸钙水泥为结合剂,研究了尖晶石细粉、活性Al2O3微粉、Cr2O3微粉对透气砖性能的影响,并研究了不同材质,狭缝形式、狭缝长度和狭缝厚度对钢水渗入狭缝的影响。结果表明:适量的活性Al2O3微粉可提高透气砖浇注料的流动性和体积密度;尖晶石可显著改善试样的抗热震性能,但加入量过大会影响材料的高温体积稳定性,并恶化抗渣性能;Cr2O3微粉对材料的流动性和抗热震性能影响不显著,但可提高其抗渣性能。透气砖材质、狭缝形式和狭缝长度对狭缝渗钢的影响不明显,但狭缝厚度会显著影响钢水在狭缝中的渗透行为。与条形缝相比,环形缝可改善透气砖的透气性能,提高透气砖的使用寿命,吹通率达到了100%。 相似文献
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为了探讨天然气反吹条件下刚玉-尖晶石质钢包透气砖不能正常吹通的原因,采用XRD、SEM及EDAX对用后透气砖的物相组成和显微结构进行分析,并结合热力学计算分析天然气的碳化反应以及天然气和透气砖组分之间的反应。结果表明:采用天然气反吹时CH4分解反应造成的碳沉积和扩散,CH4和尖晶石反应引起尖晶石中MgO还原-氧化循环造成的强度降低,以及由此引起的透气砖不同部位膨胀系数的不匹配导致透气砖在精炼时头部断裂,而头部断裂导致的狭缝错位是刚玉-尖晶石质透气砖不能正常吹通的直接原因。 相似文献
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对钢包底吹用经振动成型并烧成后的刚玉-尖晶石透气砖的组成改变的研究结果进行了研究,引入富铝尖晶石[m(Al2O3):m(MgO)=85:15]的刚玉-尖晶石透气砖的抗渣性比引入接近化学计量比的镁铝尖晶石的透气砖的抗渣性提高了2.5倍。该高级刚玉-尖晶石透气砖在乌克兰4家冶金公司使用,使用结果表明,透气砖的使用寿命显著提高。 相似文献
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通过分析90 t LF钢包透气砖的损毁原因,研究了狭缝布置、狭缝宽度、双透气砖的设计应用对透气砖透气性的影响,以保证透气砖的冶金效果,并设计开发钢包透气砖砌筑新工艺以提高透气砖的使用寿命,为建立快速、协同的二次冶金平台奠定了良好基础,满足了洁净钢生产的工艺要求。 相似文献
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着对钢水洁净度要求的提高 ,钢包精炼得到了普及 ,钢包底吹氩气透气砖被日益广泛地应用于精炼工艺上。吹氩具有均化钢水 ,使夹杂物上浮 ,提高钢水质量的作用 ,透气砖作为钢包底吹供气元件起着非常重要的作用。本研究研制出了具有合理狭缝结构的烧成无水泥铝镁铬质透气砖 ,并在 2 5t转炉钢包和 45tLF精炼钢包上进行了批量使用 ,证明其使用效果良好。1 设计思路本实验以铝镁尖晶石体系为出发点进行设计。由于使用铝酸钙水泥为结合剂会导致高温下生成尖晶石和六铝酸钙 ,产生的体积效应使透气砖的尺寸难于控制 ,烧成废品率高 ,使用中也会出现… 相似文献
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正近年来,LF、VOD炉底吹氩工艺多采用狭缝式透气砖,日本TYK公司的技术人员研究了狭缝宽度、长度以及材质对透气砖抗钢液浸润性的影响。选用质量分数分别为75%的刚玉骨料、18%的Al2O3微粉、7%的铝酸钙水泥制备了刚玉质透气砖。钢液浸润试验采用回转抗渣法。其试验条件和试验结果如下:(1)固定狭缝长度为15 mm,宽度分别为0.13、0.2、0.3、 相似文献
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Damage reasons of purging plugs for refining ladle and research progress on thermal shock resistance of corundum- spinel purging plugs were summarized. Research achievements and application results of nonoxides bonded corundum purging plugs for refining ladle were briefly reviewed. The further research and developing trend of purging plugs was proposed. 相似文献
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Alumina-spinel castable has excellent refractory properties, including high volume and thermal stability, good hot strength, and excellent resistance against corrosion, erosion, and thermal spalling. Excellent refractory properties have made it a preferred lining for steel ladles, reducing the erosion and corrosion of molten metal and slag and improving the ladle life and efficiency for decades. These castables are also significant for the replacement of chrome-bearing refractories that cause several health hazards. The current review paper covers preformed and in situ spinel containing alumina castables. It focuses on the importance of these castables in the sidewall and bottom portion of the steel ladle in detail, the effect of spinel and MgO content, and the factors affecting castable properties. The review also covers the final properties of castable and the application areas of alumina-spinel castable in steel ladle, purging plugs, and RH-degasser. 相似文献
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为了实现钢包用透气砖的无铬化,以板状刚玉(6~3、3~1、≤1mm)为骨料,板状刚玉细粉(≤0.044mm)、α-Al2O3微粉(≤5μm,d50=2.01μm)、镁铝尖晶石细粉(≤0.044mm)、电熔镁砂细粉(≤0.044mm)为基质,以纯铝酸盐水泥为结合剂,将骨料和基质的质量比固定为70:30,通过研究电熔镁砂细粉加入量(其质量分数1%、2%、3%、4%、5%)对铝镁质透气砖性能的影响,研制了铝镁质透气砖,与铬刚玉质透气砖的性能进行了对比.结果表明:加入质量分数2%的电熔镁砂细粉,试样的力学性能提高,抗热震性增强;进一步增大电熔镁砂细粉的加入量,由于原位镁铝尖晶石的生成量过多,微裂纹发展成为破坏性裂纹,试样的强度急剧降低,体积密度下降,试样的加热永久线变化增大,抗热震性先增强后减小,高温抗折强度下降.通过铬刚玉质透气砖和铝镁质透气砖性能及现场试用情况的对比,认为铝镁质透气砖可代替铬刚玉质透气砖使用,实现透气砖的无铬化. 相似文献
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HE Zhongyang WANG Fenggang LIU Baikuan SHI Xubo Puyang Refractories Group Co. Ltd. Puyang China 《中国耐火材料》2008,17(4)
An introduction of the ongoing technology of ar-gon-blowing purging plugs in China was presented in this work.Gel powders were used as starting materials to enhance the high temperature mechanical properties of the purging plugs.Composite purging plug adopting ex-trusion formed gas-purging bar and slit had its surface structural design improved,which enhanced the resist-ances to thermal shock and molten steel penetration,prolonging the service life.In addition,the safety Was greatly improved by upgrading the framework and pro-duction process,enhancing the resistance to breakout.It is indicated that the developing trend is to produce pur-ging plugs of longer service life and better gas purging rate with different starting materials and structure de-signs to meet the requirements of various metallurgical processes. 相似文献
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《Ceramics International》2021,47(22):31407-31412
The magnesia-carbon bricks are used at the ladle slag line adds carbon to molten steel and thus has an adverse effect on the smelting process. Steel production enterprises hope to remove carbon from the ladle slag line. This study presents a Silica sol (SS)–magnesium aluminate spinel(MA) coating that can be applied to the surfaces of periclase–MA spinel brick (spinel brick) to improve their slag erosion resistance, facilitating the elimination of carbon from the ladle slag line. The slag corrosion resistance mechanism of a spinel brick covered with the SS–MA coating was analyzed through scanning electron microscopy and simulation using FactSage software. The results show that increasing the SS content (CSS) led to the formation of fine cracks during the coating-drying process and was detrimental to the slag erosion resistance of the coating. The optimum CSS was 20%. In the high-temperature slag erosion experiment, the MA in the coating was capable of forming solid solutions with Fe and Mn in the slag, and the nano-SiO2 in the coating interacted with the slag, increasing the viscosity of the slag and reducing its penetration. In addition, the presence of the coating extended the penetration path of the slag and reduced the contact area between the slag and the spinel brick and their chances to undergo chemical reactions, thereby protecting the spinel brick from slag erosion. The coated spinel bricks outperformed the magnesia-carbon brick in terms of slag erosion resistance, providing a basis for selecting carbon-free refractory materials for the ladle slag line. 相似文献
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