Papers by Author: Li Guo Ma

Abstract: Rheological behaviors of alumina aqueous suspension were investigated, and some methods to modify the rheological behaviors of the suspensions were studied. It was found that there is a critical solid volume fraction for alumina aqueous suspensions. When the volume fraction reaches or exceeds the critical value the suspensions show shear thinning behaviors all along, while above which the rheological behaviors of alumina suspensions change from shear thinning to shear thickening.

Abstract: The origin of the inner stress in the ceramics green bodies prepared by colloidal forming was studied. The results show that the inner stress originates from the nonuniform shrinkage during the solidification of the precursor suspension and the drying of the green bodies, and the gradients of temperature, initiator concentration and moisture are the important original factors causing the inner stress. The inner stress could result in cracks in the green bodies during debinding.