Effect of Quartz Particle Size on Sintering Behavior and Flexural Strength of Porcelain Tiles Made from Raw Materials in Uganda

The presence of quartz particle size (> ۴۵ µm) has a deleterious effect on the properties of porcelain tiles. The effect is caused by many factors including microstructure (pore) evolution after sintering. This study aims at investigating the effect of quartz particle size (QPS) on sintering behavior and flexural strength of porcelain tiles made from raw materials in Uganda. The samples were pressed at ۴۰ MPa, fired from ۱۱۵۰-۱۳۵۰ ۰C at a firing rate of ۶۰ ۰C/min, and soaked for ۱ hour. The sintering behavior was analyzed based on linear shrinkage, water absorption and Scanning Electron Microscope (SEM) micrographs. Phase identification was carried out using X-ray diffraction method. The optimal sintering temperature of ۱۳۰۰ ۰C was established, and firing to ۱۳۵۰ ۰C resulted in bloating as observed by SEM. Samples containing fine and medium QPS had a value of ۰.۴۷ % and ۰.۹۰ % water absorption respectively at optimum temperature. Pressed tiles with and those > water absorption are classified as Group BIa and BIb respectively (ISO ۱۳۰۰۶), suitable for use as floor or wall tiles. Also, the average flexural strength of ۳۳, ۱۸ and ۸ MPa was exhibited by samples with fine, medium and coarse QPS respectively. The results indicate that only samples with fine and medium QPS satisfy the requirement MPa and > ۱۲ MPa for floor and wall tiles respectively (ISO ۱۳۰۰۶).

Keywords:

Quartz , Porcelain , Sintering , Flexural Strength