CERAMIC PIGMENTS FOR HIGH-TEMPERATURE APPLICATIONS: DURABILITY CHALLENGES
Ceramic Pigments for High Temperature Applications: Durability Challenges
Our factory Jianfeng Chemical specializes in chemical production for a long time. In the ceramic pigment industry, I have been studying for many years, and I know that under high temperature applications, there are many problems in its durability. I will describe it in detail today, and hope that the same industry will learn from it.
Ceramic pigments are used in ceramics fired at high temperature. They are colorful and enhance their beauty. However, the high temperature environment is harsh, which tests the durability of pigments greatly. The first to bear the brunt is the chemical change caused by high temperature. The kiln fire is raging, and the temperature rises sharply. The chemical components in the pigments may react, causing color changes. For example, some metal oxide pigments may be oxidized at high temperature, and the valence state changes, and the color changes. The bright color of the past, baptized by high temperature, or dull, is a challenge to the chemical stability of pigments.
Furthermore, the difference in thermal expansion coefficient is also a serious problem. If the thermal expansion coefficient of the ceramic body and the pigment does not match, the degree of shrinkage of the two will be different when cooled after high temperature firing. Under the action of this stress, the pigment may fall off from the body, or cause surface cracking. Looking at ancient porcelain works, the occasional peeling of the pigment is mostly due to this. Therefore, it is crucial to find a pigment formula that matches the thermal expansion coefficient of the ceramic body.
In addition, the complex atmosphere in the kiln also affects the durability of the pigment. Oxidation and reduction atmospheres alternate, and some pigments are sensitive to it. In an oxidizing atmosphere, certain elements are easily oxidized, and in a reducing atmosphere, or are reduced, and the color is therefore fickle. Therefore, precisely controlling the atmosphere in the kiln is a key measure to ensure the color stability and durability of pigments.
In order to deal with all kinds of challenges, our factory studies day and night. Since the selection of raw materials, we strive to be pure and high-quality, and reduce the disturbance of impurities on the performance of pigments. Formulation adjustment also spares no effort to test the ratio of various elements, hoping to obtain the best formula for excellent chemical stability and thermal expansion coefficient. In the firing process, we carefully study the changes in temperature, time and atmosphere, and carefully adjust them to make the pigments play the best performance.
Although there are many challenges, Jianfeng Chemical of Ranwu Factory adheres to ingenuity and unremitting exploration. With time, we will be able to overcome the problem of durability of ceramic pigments for high temperature applications, add luster to the color of ceramics, and pass it on to future generations, forever shining.
