Development of a master sintering curve for ThO2

A master sintering curve for ThO2 containing 0.5 wt% CaO has been constructed with the help of combined-stage sintering model. The concept of the master sintering curve (MSC) has been used to calculate the activation energy for sintering for the above composition, and a value of 520 kJ/mol was obtained. The validity of MSC has been verified by the data of a few experimental runs using a high temperature dilatometer. With one temperature dependent parameter determined experimentally (Θ), it became possible to describe accurately the densification behavior of ThO2 from the early to final stages of sintering. The sinterability of powder compacts made from different powders and fabrication procedures under different thermal histories, could be characterized through the master sintering curve.