高碱熔渣侵蚀刚玉耐材的润湿特性研究

Wetting Characterization of Corundum Refractory Materials Corroded by High Alkali Slag

为探究碱性氧化物侵蚀作用对熔渣润湿行为的影响,在程序升温条件下使用摄像机记录熔渣形态变化和润湿刚玉板的过程,通过图像处理软件测量刚玉板上高碱熔渣的接触角和润湿半径,采用非线性拟合的方法建立了温度-接触角和温度-润湿半径方程,并联立了熔渣的毛细孔渗透公式得出了温度-渗透压公式,公式和实际渗透压达到较好的拟合。由熔渣在耐火材料上的形态变化和冷却后耐火材料表面熔渣铺展情况得出,熔渣在润湿过程中存在明显分层现象,三个分层界面处存在明显的颜色变化。利用XRD分析了熔渣矿物组成变化,结果表明在1400℃下熔渣形成了铁酸镁(MF)高熔点物质,造成了润湿过程中熔渣的分层现象。利用SEM-EDX分析了熔渣润湿分界处截面的微观形貌和元素含量,结果表明侵蚀深度由熔渣中心到边缘逐渐降低,侵蚀刚玉板程度和渗透压变化一致;在铺展方向上遵循Si,Ca,Fe先后顺序沉积侵蚀,解释了侵蚀作用中元素分布区域对润湿行为的影响。

In order to investigate the effects of corrosion by alkaline oxides on the wetting behavior of slag,the changes in the slag morphology and the wetting of corundum board were recorded by using a camera under programmed temperature rises.Then the contact angles and wetting radius of the high alkali slag on the corundum plate were measured by using an image processing software,and the temperature-contact angle and temperature-wetting radius equations were established by using a nonlinear fitting method.The temperature-osmotic pressure equation was derived by associating the capillary permeation equation of the slag.The fitted equation shows a better fit with the measured permeation pressure.Based on the morphological changes in the slag on the refractory and the spread of the slag on the surface of the refractory after cooling,it is found that there is obvious delamination in the slag during the wetting process,and there are obvious color changes at the three delaminated interfaces.According to the XRD results for analyzing the changes in the mineral composition of the slag,the slag forms high melting point material of magnesium ferrate at 1400℃,causing the delamination in the slag during the wetting process.By using SEM-EDX to analyze the micromorphology and elemental composition of the cross section at the slag wetting partition,it is found that the corrosion depth gradually decreases from the center to the edge of the slag,and the degree of the corrosion corundum board and the change in the osmotic pressure are consistent.In addition,the corrosion elements follow the order of Si,Ca and Fe in the spread direction,which explains the area of the element distribution in the corrosion and the effects on the wetting behavior.