Ever since the pioneer theoretical

Ever since the pioneer theoretical models [1,2] were established, the sintering processes have been intensively studied for almost half a century. One of the main purposes of these studies is to evaluate the activation energy of sintering for distinguishing the controlling mechanisms and determining the rate-limiting species. Although most of the sintering models can be used to evaluate the value of the activation energy of sintering, an Arrhenius plot of ln(ε˙T) (where ε˙ is the densification rate) versus the reciprocal of the absolute temperature is usually used for the evaluation. However, the obtained values of the activation energy are scattered even for the same material.