Influence of Quartzite Residues on the Strength of Added Red Clay Ceramics

Abstract

The incorporation of industrial residues into red clay ceramics has in past decades been used not only as a search for the alternative use of lower cost raw-materials but also an environmentally correct way of destination of polluting wastes. This work had as its objective to study the influence of incorporation of a quartzite stone residue on the mechanical strength of a red clay ceramic. Clay bodies were prepared with up to 40 wt% of the residue. These clay bodies were then uniaxially press-molded and sintered at 800 and 1050oC. The strength was evaluated by three points bend tests. The microstructural analysis was conducted by means of both optical and scanning electron microscopes. A tendency for decreasing the strength was found with the amount of incorporated residue. This was a consequence of the inert characteristic of the quartz, which is the predominant mineral in the quartzite stone, as well as the possible effect of cracks nucleated during the quartz allotropic transformation.