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摘要:采用钛粉、硅粉及天然鳞片石墨(GF)为原料,通过自蔓延高温合成法在GF表面制备TiC-SiC复合包覆层(包覆石墨)。通过Zeta电位与润湿角测试,研究了石墨表面涂覆对其分散性与水润湿性的影响。发现当石墨质量分数为38.6%时包覆石墨Zeta电位最低,达到-35.2;与GF和机械混合试样相比,包覆石墨的水润湿角最低,为27°,水分散性与润湿性最优。以石墨质量分数为38.6%的包覆石墨替代Al2O3-SiC-C浇注料中的球型沥青,研究了包覆石墨对Al2O3-SiC-C浇注料性能的影响。研究发现:随包覆石墨代替球型沥青加入量的提高,其热震后抗折强度呈现先增大后减小的趋势,当加入量(质量分数)为1%时,其热震前后的常温抗折强度最高,分别为17.5、8.5MPa,其残余强度保持率为48.6%。浇注料的高温抗折强度随包覆石墨加入量增加而提高,当包覆石墨的添加量大于1.5%时,其高温抗折强度高于添加质量分数为2%球型沥青的试样,包覆石墨加入量为2%时,高温抗折强度达到2.45MPa。 相似文献
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以电熔白刚玉为主要原料,同时加入电熔镁砂细粉、铝酸钙水泥、α-Al2O3微粉、Si O2微粉等,保持镁砂细粉与白刚玉粉总加入量一定,通过改变镁砂细粉的加入量,研究了镁砂细粉加入量对Al2O3-MgO浇注料抗渣性的影响。研究结果表明:在Al2O3-MgO浇注料中加入一定量的镁砂细粉,高温下可以形成镁铝尖晶石,从而提高浇注料的抗渣侵蚀性。当镁砂细粉加入量在2%~6%时,浇注料的抗渣侵蚀性能最好。 相似文献
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本文研究了Al2O3细粉的加入对MgO系浇注料性能的影响。在110℃×24h烘干,1500℃×3h烧成制度下,通过改变基质中Al2O3细粉的加入量,对材料物理性能和力学性能进行测试。结果表明:3%~5%Al2O3细粉的加入能显著改善MgO系浇注料的综合烧结性能:显气孔率15%~17%;体积密度3.01~3.03g/cm^3;耐压强度和抗折强度分别高达85~92MPa和12.4—14.5MPa;当Al2O3细粉的加入量大于5%时,由于材料线变化率和显气孔率的过度增大,引起材料结构的松散,导致材料强度的降低和抗渣性能的下降如:显气孔率大于20%;体积密度小于2.90g/cm^3;耐压强度和抗折强度则分别小于70MPa和10MPa。 相似文献
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利用等离子熔融技术提取硅钛合金后的缓冷尾渣为结合剂,以电熔棕刚玉颗粒、电熔白刚玉细粉(≤0.088mm)、α-Al_2O_3微粉、SiO_2微粉为主要原料,研究缓冷尾渣加入量(0、2%、4%、6%、8%)对刚玉基浇注料性能的影响。试验表明:1随着缓冷尾渣加入量的增加,浇注料的需水量增大,常温和高温烧后强度逐步增强,中温强度则逐步降低;2加入量过多不利于其热震性能和高温抗折强度的发展;3在抗渣侵蚀性能方面,加入6%缓冷尾渣试样的侵蚀指数最大,加入量4%缓冷尾渣与以4%Secar71水泥结合的浇注料,抗侵蚀性能接近;4在刚玉浇注料中缓冷尾渣的加入量4%左右为宜,不宜超过6%。 相似文献
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主要研究了MA尖晶石粉和α-Al2O3微粉加入量对MgO质浇注料性能的影响。结果表明,随着浇注料基质中MA尖晶石粉加入量的增加,试样在1100℃×3h和1550℃×3h烧后的抗折强度和耐压强度先递减而后又有所增加,试样抵抗熔渣渗透的能力加强,抵抗熔渣侵蚀的能力减弱。随着浇注料基质中α-Al2O3微粉加入量的增加,试样在1100℃×3h和1550℃×3h烧后的抗折强度和耐压强度基本上都逐步下降,试样抵抗熔渣渗透的能力加强,抵抗熔渣侵蚀的能力减弱。 相似文献
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In order to improve the physical properties and slag corrosion resistance of refractory materials for hot metal pretreatment, different contents of composite metal powders (CMP) were introduced into Al2O3-SiC-C refractory castables. The effect of CMP on the microstructure, physical properties and slag corrosion resistance of Al2O3-SiC-C refractory castables were studied. The results show that the multi scale reinforcing phases including flake crystals, rod shaped fibers, filamentous fibers and whiskers are in situ formed in the samples with addition of CMP, which result to the improvement of the cold modulus of rupture and cold crushing strength. When the addition of CMP is 6 wt.%, the high temperature modulus of rupture increases by 231%, the thermal shock resistance increases by 77% after thermal shock by water cooling 5 times and the percentage of the slag resistant area reduces by 37.2%. 相似文献
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摘要:钢中添加适量铝元素可以提高其韧性与耐腐蚀性,但在冶炼过程中会影响炉渣中Al2O3含量而改变其与现行铝镁质浇注料的界面反应,制约钢种冶炼及品质提升。因此,采用静态坩埚法开展铝镁质浇注料的抗CaO-Al2O3-SiO2渣蚀实验,并结合热力学模拟计算探究Al2O3含量(w(CaO)∶w(Al2O3),C/A)变化对耐火材料渣蚀的影响规律,得到以下结论:随着熔渣中Al2O3含量的增加,铝镁质浇注料与熔渣反应界面越易形成更厚的高熔点隔离层,将耐火材料组分向熔渣中的直接溶解转变为间接溶解,有利于提升铝镁质浇注料的抗侵蚀性;当渣中的Al2O3质量分数在32%左右时,熔渣的侵蚀性总体较弱,但当渣中的Al2O3质量分数不小于36%时,熔渣对铝镁质浇注料产生了严重的渗透性,也易造成材料变质剥落。这为面向含铝钢冶炼用耐火材料的优化设计提供参考。 相似文献
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The toughness and erosion resistance of steel can be improved by adding an appropriate amount of aluminum. However it will increase the content of Al2O3 in slag and react with the existing alumina magnesia castable, and affect smelting and quality of steel. Therefore, static crucible method was applied, corrosion experiments of the CaO-Al2O3-SiO2 slags on the alumina magnesia castable were carried out, and the influence of Al2O3 content (w(CaO)∶w(Al2O3), C/A ratio) on slag corrosion resistance was investigated by combining thermodynamic simulation. The following conclusions were obtained: with the increase of Al2O3 content in the slags, the thicker isolation layer with high melting point is easier to form at the reaction interface between alumina magnesia castable and the slags. The direct dissolution of the refractory components into the slags can be changed to indirect dissolution, which is conducive to improving the corrosion resistance of alumina magnesia castable. Nevertheless, when the content of Al2O3 in the slag is about 32 wt.%, the slag corrosion is generally weak, when the content of Al2O3 in the slag is more than 36 wt.%, the slag has serious permeability to the alumina magnesia castable, which is easy to cause the deterioration and spalling of the material. It provides guidance on the optimization and design of the refractories for Al containing steel smelting. 相似文献
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By using different particle size of fused white corundum(<74 μm,74~147 μm,>147 μm),flake graphite,solid resin,commercial alcohol,zirconia(calcium oxide as stabilizer) as the raw materials,Al2O3-C samples with the length of 850 mm,inner(alumina-graphite) diameter of 50 mm and outer(zirconium) diameter of 85 mm were prepared by cold isostatic compaction pressed at 160 MPa after prilling in granulator.An electric field was applied to Al2O3-C refractory and the effect of current intensity(0.5 A,1 A and 5 A) on ... 相似文献
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镁砂和硅微粉加入量对Al2O3-尖晶石浇注料性能的影响 总被引:1,自引:0,他引:1
在保持MgO化学成分总量不变的前提下,研究了镁砂细粉、SiO2含量对Al2O3-尖晶石浇注料性能的影响。结果发现:适量的镁砂细粉和SiO2微粉能提高浇注料强度,降低显气孔率,提高抗渣渗透性。 相似文献
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为适应精炼钢包用耐火材料轻量化的发展需要,采用两步烧结法向Al_2O_3-MgO-CaO系复相耐火材料中添加La_2O_3,并对该耐火材料的抗LF精炼渣侵蚀性能进行了研究。结果表明,添加的La_2O_3优先固溶入Al_2O_3-MgO-CaO系复相耐火材料的晶相CaO·6Al_2O_3中,促使CaO·6Al_2O_3晶胞产生晶格畸变,有效抑制了CaO·6Al_2O_3晶粒沿基面的异常长大,进而有效地促进了Al_2O_3-MgO-CaO系复相耐火材料的烧结致密化。当添加La_2O_3的质量分数为4%,在1600℃保温2h烧成后,试样的气孔率由占总体积分数的19.2%下降至6.1%,体积密度由2.78g/cm3上升至3.18g/cm3,制得了含MgO·Al_2O_3、CaO·2Al_2O_3、CaO·6Al_2O_3晶相且呈现交织分布、显微结构致密的Al_2O_3-MgO-CaO系复相耐火材料,其抗LF精炼渣侵蚀性能与同等致密度的Al_2O_3-MgO质耐火材料相当。 相似文献