摘要
在电熔镁铬砂的质量分数分别为50％（3～1mm）、13％（≤1mm）和37％（≤0．088mm）的镁铬砖基础配方中，分别外加2％的纯氧化铬、α-Al2O3、氧化锆、锐钛矿、α-Al2O3（1％）＋锐钛矿（1％），以3％亚硫酸纸浆废液（外加）为结合剂，混匀后在200MPa压力下成型为Ф50mm×50mm的圆柱试样和中心有Ф20mm×20mm孔洞的坩埚试样，110℃干燥箱中烘6h后，在高温隧道窑中于1800℃保温3h烧成。检测烧后试样的显气孔率，并用XRD分析试样的物相组成，用光学显微镜分析1640℃保温4h静态渣侵试验后试样的显微结构。结果表明：各种添加物的加入使镁铬砖的抗渣性和抗热震性都有所提高。添加物提高镁铬砖抗渣性的顺序为：α-Al2O3＋锐钛矿〉α-Al2O3〉氧化铬〉锐钛矿〉氧化锆；添加物在提高镁铬砖抗热震性上的顺序为：α-Al2O3＋锐钛矿〉α-Al2O3〉氧化锆〉锐钛矿〉氧化铬，其中α-Al2O3＋锐钛矿复合添加物不但使镁铬砖具有较强的抗渣性，而且抗热震性也同步提高，是提高镁铬砖性能的理想添加物。
Chromia （2 wt%）,α-Al2O3（2 wt%） ,zirconia （2 wt%） ,anatase （2 wt% ） and α-Al2O3（1 wt%） ＋ anatase （1 wt%） were respectively added into fundamental formula of magnesia -chrome brick, which is com- posed of electrofused chrome magnesite 3 -1 mm 50 wt%, ≤ 1mm 13 wt%, ≤0. 088 mm 37 wt%. The compounds were mixed evenly with 3 wt% binder of sulfurous-acid-pulp waste liquid,then pressed into cylinder specimens of Ф50 mm ×50 mm with and without a central hole of Ф20 mm ×20 mm under pressure of 200 MPa. After dried at 110 ℃ for 6 h,the specimens were fired at 1 800℃ for ：3 h in high-temperature tunnel kiln. Apparent porosity was measured for the fired specimen, phase composition was examined with XRD,and microstructures of the specimens after static slag corrosion experiment at 1640 ℃ for 4 h were analyzed with optical microscope. The results show that slag resistance and thermal shock resistance of the bricks are improved by the four additives. The order on improving slag resistance is：α-Al2O3 ＋anatase 〉 α-Al2O3 〉chromia 〉anatase 〉zirconia,and the order on improving thermal shock resistance is：α-Al2O3 ＋ anatase 〉α-Al2O3 〉zirconia 〉anatase 〉chromia. The compound of α-Al2O3 ＋anatase is the optimum additive because it improves both slag resistance and thermal shock resistance of the magnesia -chrome brick.
出处
《耐火材料》
CAS
北大核心
2008年第2期120-123,共4页
Refractories
关键词
添加物
镁铬砖
抗渣性
抗热震性
Additive, Magnesia-chrome brick, Slag resistance, Thermal shock resistance
