Compaction behavior of dry granulated red wall tile paste prepared using raw materials from Rio de Janeiro State

Abstract

This work presents the results of a study about on the compaction behavior of a dry granulated red wall tile paste. The ceramic paste was formulated using raw materials of the Rio de Janeiro state. The raw materials were dry-ground and then microgranulated using a mixer of high intensity. The produced powder was characterized regarding X-ray diffraction, chemical composition, granule size analysis and morphology. The moisture content of the granulated powder (moisture mass/dry mass) varied between 0 and 10%. The granulated powder with different moisture contents was submitted to cold compaction process using a uniaxial die-pressing technique with compaction pressure up to 60 MPa. The compaction behavior of the wall tile powder was evaluated through compaction response and compaction rate diagrams. The development of the microstructure during compaction process was followed by scanning electron microscopy. The experimental results show that the green density of the tile compacts behaves as a function of moisture content. It was also found that the compaction process is ruled, at the applied pressure range, by two dominant mechanisms including granule rearrangement and plastic deformation. The rate of densification is high initially, but then decreases rapidly for pressures above apparent yield pressure (2.44 - 5.38 MPa). In addition, the better compaction efficiency was found to be influenced by the moisture content.