How ceramics are fired

Raw materials are the foundation, and firing is the key. In the ceramic production process, firing is one of the crucial processes. The firing process of ceramic products is to perform high-temperature treatment on the formed, glazed, and dried ceramic body under certain temperature and atmosphere conditions, causing a series of physical and chemical changes, forming a certain mineral composition and microstructure, and ultimately obtaining various characteristics of ceramic products. The body undergoes a series of physical and chemical changes during the firing process, such as expansion, contraction, gas generation, and liquid phase appearance The disappearance of old crystal phases, the formation of new crystal phases, etc. The content and degree of changes occur under different temperature and atmosphere conditions, resulting in different mineral compositions and microstructures, which determine the different quality and performance of ceramic products.
The glaze layer on the surface of the body undergoes various physical and chemical changes during the firing process, ultimately forming a glassy substance with various physical and chemical properties and decorative effects. The common firing process can be divided into one firing and two firing. Once fired, it is the process of applying glaze to the green body, drying it, and then firing it into a product at high temperature in a kiln. Twice firing refers to the process of drying the unglazed body and then firing it before applying glaze, followed by a second firing (glaze firing). The one-time firing process simplifies the process, reduces heat loss during firing, and improves the strength of the body through two rounds of firing, which is beneficial for the mechanization and automation of subsequent processes, reduces damage, and improves the quality of the glaze. During actual production, the selection should be based on the specific situation of the product.
The firing process is carried out in a specialized thermal equipment called a kiln. There are many types of kilns, and the selection should be based on different products. At the same time, various kiln tools are often used during firing. Reasonable selection and use of kiln tools are also of great significance for improving product quality, saving energy, and reducing production costs. There are many factors that affect firing, and if not properly controlled during the firing process, it not only wastes fuel, but also directly affects product quality, and even causes a large amount of waste, bringing undue losses to the enterprise. Therefore, only by mastering the variation law of the billet during the high-temperature firing process, selecting and designing the kiln correctly, scientifically formulating and implementing the firing system, and strictly implementing the loading and firing operation regulations, can we improve product quality, reduce fuel consumption, and achieve good economic benefits.