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采用座滴法测定固液间接触角，分别对镁碳质基片及基片中的两种主要组元与LF精炼渣之间的润湿性进行了研究，并从润湿性角度研究了镁碳砖损毁机理。研究表明，在精炼温度下，熔渣对石墨均呈不润湿状态，温度越低越不容易润湿。而熔渣对MgO组元呈完全润湿状态。熔渣与镁碳质基片间的接触角在温度为1460～1480℃时存在明显转折，在转折点温度以下，MgO和碳的反应受到抑制，熔渣对基片保持不润湿状态。在转折点温度以上，镁碳质基片中的MgO和碳发生反应生成镁蒸汽和CO气体。该反应导致基片内碳质量分数减少，熔渣对基片的接触角迅速下降，最终呈完全润湿。当熔渣与基片间的接触角小于90°时，熔渣将对基片产生明显渗透作用。MgO与碳反应形成的孔隙成为熔渣渗透的主要通道。熔渣渗透到镁碳质基片内部的未反应层时，由于两者之间的不润湿性及较少的孔隙阻碍了熔渣的进一步渗透。

In order to investigate the wear mechanism of MgO-C brick from the point of wettability,the sessile drop method was employed to measure the contact angle between liquid and solid phase. The wettability between MgO-C sub-strate as well as two main components in the substrate and LF refining slag was studied. At the refining temperature, graphite substrate was not wetted by the molten slag,and the lower temperature it was,the more non-wetting it became. While the MgO component was completely wetted by the slag. There was an obvious turning point of contact angle be-tween molten slag and MgO-C substrate in the range of 1 460℃and 1 480℃. Below the turning point,the reaction be-tween MgO and C was restrained for the lower temperature,and the MgO-C substrate kept un-wetted by molten slag. Above the turning point,the MgO reacted with carbon,and Mg vapor and CO gas were generated. The carbon content was reduced for the reaction,leading to the fast decrease of contact angle between molten slag and substrate. Once the contact angle was smaller than 90° ,the molten slag penetrated into the substrate. The pores formed by the reaction be-tween MgO and carbon became the main channel for the penetration of slag. When the slag penetrated into the substrate and reached at the interface of unreacted layer,the non-wetting property between the slag and unreacted layer and few pores prevented the further penetration of slag.