New observations in creep behaviour of ramming paste in aluminium electrolysis cell

Abstract

Creep of ramming paste was studied from ambient to operational temperature in order to characterize its mechanical behaviour as used in the peripheral joint of aluminium electrolysis cells. Two types of uniaxial creep test over a specified stress level were performed on two inch samples: tests at room temperature for samples baked at different temperatures and test at temperatures close to the sample baking temperature. It is concluded that at certain baking temperatures and given stress level, three types of creep, called primary, secondary and tertiary, take place successively. In addition, at lower baking temperatures (200°C), the creep level is larger in comparison with creep at higher baking temperatures. Also, for specified baking temperature, creep strain obtained by high temperature testing is larger than creep strain obtained by room temperature testing. These results give new insights on the ramming paste behaviour in aluminium electrolysis cell.