Fly ash-based frit as a sintering aid for ceramic body

Tóm tắt

Coal fly ash is characterized by high silica and alumina contents, making it suitable as a raw material for alumosilicate ceramics. However, direct use of fly ash reveals obstacles such as high porosity, black core, cracking, and swelling. This work synthesized frit by melting a mixture of fly ash, quartz, limestone, and soda. TG-DSC analysis showed that the glass transition point of the frit occurs at approximately 600 degrees Celsius. Ceramic bodies from raw mixes containing various frit amounts were prepared and characterized. The results showed that with 4% being frit, the firing temperature could be reduced by 30 degrees Celsius, along with decreased water absorption and increased flexural strength. Besides, no swelling, cracks, or black cores occur. These observations indicate that fly ash-based frit is viable a sintering aid in ceramic production.