Experimental Study on Thermal Shock Resistance of Magnesia Carbon Brick

Abstract

In this paper, five kinds of magnesia carbon refractories commonly used in the metallurgical industry were selected to explore their thermal shock resistance. The experiment results showed that the maximum residual flexural strength of sample 2# was 8.07 MPa after three thermal shock cycles under the stress of not more than 0.3 MPa, representing the best thermal shock resistance according to the standard. The accuracy of this result was verified through the tests for the linear expansion performance, ratio of high-temperature flexural strength (Re) to Elastic modulus (E). Sample 2# showed a basically identical linear expansion rate with that of the high-carbon sample at the test temperature of 1200–1500 ℃. The Re/E index of sample 2# was relatively high at high temperatures. The comprehensive analysis identified that sample 2# performed the best thermal shock stability. Therefore, sample 2# can serve as qualified refractories of a converter bath.