抄録
Utilization of common clay in admixtures with various other substances for fabrication of utility goods and art objects are widely in practice. However, slip casting of slurries of such crude materials poses several problems in shaping of green bodies because of poor reproducibility due to lack of sufficient knowledge on the rheological properties of those suspensions. In the present investigation, suspensions containing common clay, quartz and fly ash have been selected for evaluating rheological properties of those suspensions with an ultimate objective of preparing slips with reproducible castability. Newtonianity of those suspensions were evaluated by rotational type viscometer and an attempt was made to explain the behavior of suspensions in terms of Newtonian factor ‘n’ consistency factor ‘k’ and viscosity ‘η’. Different factors responsible for affecting ‘n’, ‘k’ and ‘η’ were analyzed and their inter relationship established. It was found that the suspensions were of pseudo plastic in nature with a marked tendency towards becoming Newtonian. Rheological parameters like ‘n’, ‘k’ and ‘η’ were found to be extremely electrolyte sensitive. The entire phenomenon was explained by assuming floc structure and deflocculations were interpreted in terms of electrolytic as well as mechanical forces. Castability of suspension was found to be related to ‘n’, ‘k’ and ‘η’.
