Prediction of Fracture Toughness of Magnesia-Carbon Bricks Based on Fractography

摘要

The introduction of carbon greatly improves the high temperature performance of magnesia bricks. In order to explore the influence of carbon content on the fracture toughness and the fracture mechanism of magnesia-carbon bricks, two different carbon content(10wt% and 14wt%) magnesia-carbon bricks were investigated in this work. The fracture toughness and microstructure were characterized by fractal analysis of fracture surface and scanning electron microscope respectively. The results indicated that the strength of magnesia-carbon bricks was strengthened with the carbon content increasing. It was demonstrated that magnesia-carbon brickswith the higher carbon content presented higher fracture toughness as a consequence of lower apparent porosity andcompact bonding between matrix and magnesia aggregates.