CRYSTALLIZATION OF MOLD POWDERS USED IN THE CONTINUOUS-CASTING OF STEEL

Mould powders used in the continuous casting of steel play an importan t role in the heat transfer and lubrication between the liquid metal s trand and mould. A range of industrial fluxes was investigated, each s ample being decarburized and milled prior to DTA. On heating, the powd ers undergo silicate crystallization producing exotherms in the range 600-degrees-1000-degrees-C, before melting. The activation energy of c rystallization (E(a)) was determined from the peak shifts of each flux heated at different rates, and ranged from 100-450 kJ/mol. E(a) value s increased with flux viscosity and decreased with basicity, suggestin g that DTA can be applied to mould powder evaluation for use in contin uous steel casting.