提高镁碳质出钢口管砖使用寿命的途径

Measures to enhance the performances of MgO-C tapping hole brick

将粒度为3-1mm和≤1mm、w（MgO）=98%的电熔镁砂,w（C）=97%的鳞片石墨以及金属铝粉（≤0.088mm、w（Al）〉97%）,硅粉（≤0.088mm、w（Si）〉98%）,碳化硅粉（≤0.088mm、w（SiC）〉97%）和碳化硼粉（≤0.043mm）等抗氧化剂按一定比例混练成型为110mm×350mm试样,再将试样加热至1400℃保温2h后研究了复合抗氧化剂的效果和机理;然后通过改变配料中的颗粒级配工艺,研究了材料常温和中温处理后的性能以及材料的显微结构。结果表明：采用适当的复合抗氧化剂Al-Si的效果最好;将传统的3级配料优化后,按照颗粒级配方程设计的4级配料方法制备的试样,可以明显提高材料的中温性能,材料致密程度也明显改善。在此研究的基础上,实际制备的镁碳质出钢口管砖的实际试用结果比以前材料的寿命提高了50%左右。

Fused magnesite （3-1 mm and ≤1 mm, w（MgO） 〉98%） and flaky graphite （w（C） 〉97%） as main starting materials, aluminum powder （ 4 0.088 mm, w（Al） 〉 97% ）, Si powder （≤ 0.088 mm, w（Si） 〉 98%） ,SiC powder （40.088 mm, w（SiC） 〉97% ） and B,C powder （40.043 mm） as composite antioxidants Were mixed with certain proportion and pressed into specimens with size of Ф110 mm ×350 mm. The specimens were fired at 1 400 ℃ for 2 h to research the effect and mechanism of the composite antioxidants. The properties at normal and middle temperatures and microstructure of specimens were researched by changing the particle size composition from 3 levels to 4 levels. The results showed that the effect of the proper AI -Si complex antioxidant was the best. The properties at middle temperature and the dense degree of the specimen with 4 levels were obviously improved. Based on this study, the service life of MgO -C tapping hole brick was increased by more than 50% in practice.