Estudo do comportamento das propriedades físicas e mecânicas com a variação da pressão de compactação de peças cerâmicas obtidas a partir do rejeito do granito branco marfim

Abstract

The ornamental rock industry has witnessed remarkable global growth, with Brazil standing out as one of the largest producers and exporters in this sector. However, this growth has led to the significant generation of waste resulting from extraction and processing activities. A substantial portion of these rejects is disposed of into the environment without adequate care to minimize or eliminate potential contamination by pollutant components. Repurposing the byproduct presents an opportunity to mitigate environmental impacts and reuse them in the industry. Based on this information, this study aimed to investigate the technological feasibility of the reject from white ivory granite as a raw material for artifacts obtained through ceramic processing, utilizing analyses of physical and mechanical properties. The granite powder was chemically characterized through Energy Dispersive Spectroscopy (EDS). The samples were compacted under four compaction loads (20 kN, 40 kN, 60 kN, and 80 kN) and sintered at a temperature of 1140°C. Subsequently, tests were conducted to determine physical properties (volumetric variation, real density of loose grain, apparent specific density, and porosity) and mechanical properties (Rockwell B hardness and tensile strength by diametral compression). The results indicated that visually, the sintered specimens exhibited a brown hue and a matte appearance, and there was no significant variation in the volume of the sintered pieces. Porosity values decreased with increasing compaction load, approaching stability. Concerning mechanical properties, tensile strength by diametral compression and Rockwell B hardness increased with an increase in compaction load. Tensile strength exhibited a large standard deviation under both compaction loads, while hardness showed a tendency towards stability. Thus, it was possible to conclude that properties vary with increasing compaction load but tend to stabilize with further increments.