Obtenção e caracterização de engobes com adição de resíduos do mármore para revestimento cerâmico

Abstract

Considering the constant technological growth and the needs of production techniques in the area of ceramics that advance together , we sought in this study to evaluate formulations of ceramic bodies with added residue marble instead of quartz obtain ceramic engobes. Normally the engobe is applied to the part before the enamel, forming a sublayer that will mitigate different compositions between the two bodies ( substrate and glaze ) wishing to join , limit the risk of appearance of defects in the glaze, hide the color of the substrate where necessary to waterproof the ceramic part before enamelling and permit the use of thinner layers of glazes which reduces the overall cost. Clear burning clay, phosphate, quartz, kaolin, zircon, feldspar, frit, carboxymethylcellulose (CMC) and the homogenized residue marble masses, six formulations of ceramic bodies varying proportions of the following raw materials were prepared. To evaluate the physical and mechanical properties, technological tests of linear shrinkage, water absorption, apparent porosity, bulk density and flexural strength of the ceramic bodies were made. The fracture surface morphology was characterized by scanning (SEM) electron microscopy. It can be seen that some formulations showed satisfactory results, in which some values suggested by ABNT NBR 13.818 were achieved - ceramic tiles - Requirements and test methods (ABNT , 1997) and the European Standard EN 100, highlighting the potential for substitution up to 10 % of the residue by quartz marble ceramic formulation for engobes thus minimizing the environmental impact caused by the improper disposal of waste , reducing the final costs and increasing the range of raw materials for the coatings industry