Creep testing and visco-elastic behaviour reseach on carbon cathodes during aluminum electrolysis

An apparatus to measure compressive creep in carbon cathode materials has been developed. Short-time creep were measured at 30 degrees C, 965 degrees C and during aluminum electrolysis at 965 degrees C. The creep strain increases with stress, indicating that the creep behavior is of the stress dependency. The ranking from low to high creep was at 30 degrees C<965 degrees C<during aluminum electrolysis at 965 degrees C. The integral creep conctitutive mdoel were estalished based on the relevant rheological mdoel. The results indicate the proposed rheological model can discribe the creep rate at the first stage and the stady-state stage on the creep strain curves. Simultaneously, the viscous coefficents denoting the viscous behavior in visco-elastic constitutive model were determined by taking use of the creep testing data.