Effect of andalusite aggregate on thermal shock resistance of mullite castable for desulphurization injection lance

摘要

Effect of andalusite aggregate addition on thermal shock resistance of mullite castable heat-treated at 800 deg C and 1400 deg C was studied respectively by XRD analysis, EDA, SEM and by using water cooling method, in which some andalusite aggregate were added into desulphurization injection lance made of mullite castable. The results showed that the thermal s hock resistance of the castable was improved with the increase of andalusite addition. The reason is that the cracks formed by differences of thermal expansion coefficient between andalusite aggregates and matrix in castable stop the prop a gating of cracks formed during thermal shock. Meanwhile, the cracks also decreased the MOR of the fired specimens.