Influence of Processing Variables on Clay-Based Ceramic Formulations

• Published in: Materials research (São Carlos, São Paulo, Brazil) Vol. 22; no. 3; p. 1
• Main Authors: Figueirêdo, Julliana Marques Rocha de, Silva, José Rodrigo Sousa, Neves, Gelmires de Araújo, Ferreira, Heber Carlos, Santana, Lisiane Navarro de Lima
• Format: Journal Article
• Language: English
• Published: Sao Carlos Universidade Federal do Sao Carlos, Departamento de Engenharia de Materiais 01-01-2019; ABM, ABC, ABPol; Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol)
• Subjects: Aluminosilicates; Aluminum silicates; Bentonite; Ceramics; Ceramics industry; clay; ENGINEERING, CHEMICAL; Extrusion; Firing; Formulations; Heat treatment; Heating rate; MATERIALS SCIENCE, MULTIDISCIPLINARY; Maturation; Mechanical properties; METALLURGY & METALLURGICAL ENGINEERING; Mullite; Needles; Plastic properties; Process parameters; processing variables; Raw materials; Statistical analysis; Water absorption; processing variables; mechanical properties; clay
• ISSN: 1516-1439; 1980-5373; 1980-5373
• DOI: 10.1590/1980-5373-mr-2018-0548

The properties of ceramic materials and microstructural changes are dependent on the raw materials from which they are made and on the manner in which they are processed, from the composition to the established thermal treatment, heating rate, and firing temperature. In this study, the influence of some processing parameters (formulation, maturation time, and firing temperature) on the physical-mechanical properties and microstructural aspects of ceramic pieces produced from natural aluminosilicates was investigated. Because Brazil does not have many quality ball clays reserves, bentonite was included as a plasticizing agent in this study. The formulations were submitted to maturation for a period of one to four weeks and their characteristics were determined to evaluate plasticity. Following this, the specimens were extruded and subjected to heat at temperatures of 1200, 1300, and 1400ºC. The physical-mechanical properties determined were: water absorption, linear retraction, and flexural strength. Statistical analysis was applied. The results showed that, for the analyzed masses, neither the maturation time nor the physical and mechanical properties analyzed had influence on plasticity. The firing temperature was the factor that generated the greatest alteration in results, increasing the mechanical resistance and altering the size and interlocking of the mullite needles.