Studies on the mechanism of compaction of Ceramic mixes of dry press consistency

Abstract

A study has been made of the compaction of ceramic mixes of dry press consistency adopting the traditional fabrication methods of tamping and pressing viz. (i) bumping under the mixe’s own weight, (ii) ramming with an A.F.M.S. rammer, (iii) pressing in a die in a hydraulic press and (iv) by impacts from a forge hammer. In these methods of compaction increase in bulk density follows the relationship:- dBD/dp =K (BD-BDp) where dBD is the increment in bulk density with increment in work factor dP and BD is the maximum possible increment in bulk density and BDp is the increment under work factor P and K is a proportionality constant. Analysis of the data indicates that the compaction occurs by two simultaneously operating mechanisms. It is suggested by the authors that these mechanisms may be (i) compaction by sliding together of particles and (ii) compaction by the entering into available voids of fines produced by mutual attrition of contribution of the two mechanisms varies with the methods of compaction. In the present study, trends are traceable with some definiteness only in case of compaction by bumping under the mixe’s own weight and when mix is rammed with light blows from the A.F.M.S.