Per: FLANELSON MACIEL MONTEIRO (INSTITUTO FED EDUCACAO, CIENCIA E TECN RIO GRANDE NORTE), Bruna Pereira do Nascimento Souza (IFRN), Anna Beatriz Almeida Leandro da Costa (IFRN)
Abstract:
Clays are essential raw materials for the production of ceramics, being popularly known for their coloration after the sintering process, where basically they have red, white and their variations. The red color, usually found in bricks, tiles and tiles, is acquired by the iron oxide (Fe2O3) present in the clay material. On the other hand, the white coloration is a result of the low amount of Fe2O3 and the high percentage of aluminum oxide (Al2O3). However, despite having a vast potential for use in the ceramics industry, the kaolinite clays, known as white burn, are not easily found by industry. The main challenge to increase the quantity of pieces produced with this type of clay is the prospecting of new deposits. Therefore, the objective of this work is to study the technological properties of a kaolinite clay from the municipality of Boa Saúde - RN. The work was started with the sampling process and the processing of the material. The clay was collected, destorated, comminuted and sieved in an ABNT 200 mesh (74mm) sieve. After this step, thirty (30) test specimens were made, for that a hydraulic press with a pressure of 21MPa was used. The sintering process was carried out in a muffle furnace without protective atmosphere at temperatures of 850°C, 950°C and 1050°C, with a heating rate of 10°C/min and a 60 minute isotherm plateau. At each temperature ten (10) specimens were sintered. In order to evaluate the technological properties, the following tests were used: water absorption (AA%), linear retraction (RL%), fire loss (PF%), apparent porosity (PA%) and apparent specific mass ). At the end of the characterization process, the clay presented a beige coloration and variations of this tonality, corroborating with the result of the EDX analysis that showed a low amount of iron oxide (Fe2O3), soon defining it as being of white burn. The results of the technological tests showed that the ceramic pieces have properties that point to the fabrication of structural ceramics and coatings.
