Several authors have proposed such

Several authors have proposed such models. Ashby’ recognized the similarity in form of the single-stage models, and attempted to integrate them in his sintering maps. DeHoffx used a cell geometry to describe microstructural evolution during sintering but did not explore the effects of varying microstructural geometry on sintering kinetics. Johnson9-”has prcsented a combined-stage model of sintering obtained by inspection; a derivation of this model is provided in the present work. Wang and Raj utilized a generalized sintering equation in their study of sintering activation energies; they did not, however, discuss its derivations or implications. Zhao and Harmer‘ derived and applied a simplified sintering model to final-stage sintering of idealized alumina compacts. Chu et L I [ . ’ ~ recently proposed another general model in which simultaneous coarsening and densification were considered. These will be discussed in greater detail below.