基于数字图像相关法的铝镁质耐火材料抗侵蚀性能研究

Corrosion Resistance of Alumina Magnesia Refractory Based on Digital Image Correlation Method

钢渣侵蚀是耐火材料在服役过程中的主要损毁形式之一,实际侵蚀过程难以直接观察。传统上采用蚀后分析方法来评价耐火材料的抗侵蚀能力和了解侵蚀机理,但易缺少过程信息,导致结果存在偏差。因此,本文在高温可视化系统基础上,结合数字图像相关法,选取三种典型钢渣,开展铝镁质耐火材料的渣蚀行为研究,并探讨了不同钢渣及热处理温度对材料抗侵蚀能力的影响。结果表明:碱度越低的熔渣对铝镁质耐火材料的侵蚀越严重;对铝镁质耐火材料进行1 000℃以上的热处理,可有效提高材料的抗侵蚀能力;通过数字图像相关法可以获得随时间变化的平均应变曲线和侵蚀应变云图,其中平均应变曲线可以对比铝镁质耐火材料对不同钢渣的抗侵蚀能力,侵蚀应变云图可以反映侵蚀的演变过程,两者为耐火材料渣蚀过程的表征提供了量化指标。

Steel slag corrosion is one of the main damage forms of refractory during service, and it is hard to observe the actual corrosion process directly. Traditionally, postmortem analysis is used to evaluate corrosion resistance capacity and to understand corrosion mechanism of refractory. However, the lack of process information in postmortem analysis results in deviation. Therefore, on the basis of high temperature visualization system and digital image correlation(DIC) method, three typical steel slags were selected to carry out the corrosion corrosion behavior experiments of alumina magnesia refractory, and the effects of different steel slags and heat treatment temperatures on the corrosion resistance capacity of refractory were discussed. The results show that the slag with lower basicity has more serious corrosion on refractory. The corrosion resistance capacity of alumina magnesia refractory can be effectively improved by heat treatment above 1 000 ℃. The average strain curve and corrosion strain nephogram over time can be obtained through DIC method. The average strain curve is used to compare the corrosion resistance capacity of alumina magnesia refractory to different steel slags, and the corrosion strain nephogram reflects the evolution process of corrosion. The above two provide quantitative indicators for characterizing the slag corrosion process of refractory.