| With the development of the steel industry, secondary refining technology is used more and more extensively, especially the progress and development of LF, CAS, RH, VD, AOD refining technology and equipment. Correspondingly, the condition of use of refractories requires higher and higher. The purging plug for ladle has poor toughness and poor thermal shock resistance, which seriously restrict the life of the purging plug for ladle. This paper deals with high toughness metal Cr material, which is composed of corundum-spinel purging plugs to get good thermal shock resistance, wind-rate, long service life as a new generation of advanced technology purging plug products.First, the aluminum thermal reaction of Cr + Al2O3 is investigated in this work. Results showed that when the amount of the thinner Al2O3 and Cr2O3 (weight percentage) were 10% and 30%, the diameter less than 1μm for Cr phase is available at the experimental temperature TC = 1373K.Several ways to add metal chromium powders were used, including direct addition (J), surface oxidation process (M), surface coating (A), surface passivation (H) and aluminum thermal reaction new generation (F). It is found that when the addition of chromium metal powder is 7% by the surface oxidation process (M), more dense structure, the best oxidation resistance properties, high bending strength at room temperature, high bending strength and high residual rates of bending strength after thermal shock are obtained.The difference is small in the evaluation of metal Cr toughening thermal shock performance of the purging plug for ladle by using the both ways of non-uniform heating - cooling (simulation of the actual application conditions) and even heating - cooling (traditional method).
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