發(fā)布時間：2018-06-15 03:54

  本文選題：剛玉-尖晶石澆注料 + 泡沫法��； 參考：《武漢科技大學》2015年碩士論文

【摘要】：剛玉-尖晶石耐火澆注料因其優(yōu)異的高溫服役性能作為鋼包工作襯材料得到廣泛的運用。隨著鋼包精煉技術(shù)的提升，鋼水的出鋼溫度也相應提高，致密的剛玉-尖晶石澆注料具有較高的導熱系數(shù)，會增加煉鋼過程中的能耗。但是要降低材料的導熱系數(shù)其顯氣孔率將顯著提高，勢必會影響材料對熔渣和鋼水的侵蝕和滲透作用。為此，本論文擬利用泡沫法制備具有孔徑分布均勻且多為封閉氣孔、體積密度可控的多孔材料的特點，分別將泡沫引入到剛玉-尖晶石澆注料的基質(zhì)與骨料中，設(shè)計并制備具有多孔結(jié)構(gòu)的剛玉-尖晶石澆注料，旨在保持力學性能和抗渣性能的前提下，改善其隔熱保溫性能，為鋼包內(nèi)襯耐火澆注料的輕量化提供理論依據(jù)。具體研究內(nèi)容及結(jié)果如下： （1）將泡沫直接引入到基質(zhì)中制備出具有多孔結(jié)構(gòu)的剛玉-尖晶石澆注料，系統(tǒng)研究了泡沫加入量對材料的微觀結(jié)構(gòu)、常溫物理性能、高溫服役性能以及導熱性能的影響。結(jié)果表明，，當泡沫加入量為200mL/kg時所制備的試樣綜合性能最接近常規(guī)剛玉-尖晶石澆注料，但導熱系數(shù)有明顯下降。其體積密度在110℃×24h烘后為3.03g·cm-3，1550℃×3h熱處理后為2.94g·cm-3；常溫抗折強度和耐壓強度在110℃×24h烘后分別為10.1MPa和67MPa，1550℃×3h熱處理后分別為27.1MPa和144MPa；在水冷熱震1次和水冷熱震3次后的殘余抗折強度保持率分別為29.0%和16.6%；與未加入泡沫試樣相比，其抗渣性基本沒變化；在1000℃時試樣的導熱系數(shù)為0.788W/m·K，相對于未加入泡沫試樣下降了10%。 （2）采用濕法造粒法，向其中引入泡沫，設(shè)計制備了具有核殼結(jié)構(gòu)的多孔剛玉球。結(jié)果表明，剛玉球經(jīng)1800℃×3h熱處理后的平均孔徑為6.47μm；其未破碎的顯氣孔率和閉口氣孔率分別為10.9%和13.6%，而破碎后的顯氣孔率和閉口氣孔率分別為15.5%和6.6%；剛玉球的筒壓強度為443.3MPa。 （3）將所制備的具有核殼結(jié)構(gòu)的多孔剛玉球取代板狀剛玉骨料，基質(zhì)不變制備了剛玉-尖晶石澆注料。結(jié)果表明，試樣永久線變化率均呈現(xiàn)出微膨脹現(xiàn)象；試樣在110℃×24h烘后的體積密度為2.96g·cm-3，在1550℃熱處理后為2.90g·cm-3；在110℃×24h烘后的常溫抗折強度和耐壓強度分別為10.3MPa和87MPa，1550℃×3h熱處理分別后為28.7MPa和172MPa；雖然試樣的侵蝕指數(shù)比使用板狀剛玉骨料制備的剛玉-尖晶石澆注料高，但其滲透性能相對較優(yōu)；在1000℃時試樣的導熱系數(shù)為0.753W/m·K，相對于板狀剛玉骨料制備的剛玉-尖晶石澆注料的導熱系數(shù)下降了13.9%。
[Abstract]:Corundum-spinel refractory castables are widely used as ladle lining materials for their excellent high temperature service performance. With the improvement of ladle refining technology, the tapping temperature of molten steel increases accordingly, and the dense corundum spinel castable has higher thermal conductivity, which will increase the energy consumption in the steelmaking process. However, to reduce the thermal conductivity of the material, its apparent porosity will be significantly increased, which will inevitably affect the erosion and permeability of the material to molten slag and molten steel. Therefore, the foam method was used to prepare porous materials with uniform pore size distribution and controlled volume density, and foam was introduced into the matrix and aggregate of corundum spinel castable, respectively. The corundum spinel castable with porous structure was designed and prepared to improve its thermal insulation and thermal insulation performance under the premise of maintaining mechanical properties and slag resistance and to provide a theoretical basis for lightening the refractory castable in ladle lining. The specific research contents and results are as follows: (1) foam was introduced directly into the matrix to prepare corundum spinel castable with porous structure. The effect of high temperature service performance and thermal conductivity. The results show that when the foam content is 200mL / kg, the comprehensive properties of the samples are the closest to the conventional corundum spinel castable, but the thermal conductivity decreases obviously. The bulk density was 3.03g / cm ~ (-3) after drying at 110 鈩

本文編號：2020514