Process optimization for ceramics production

摘要

Ceramics are used widely in the industries with high temperatures. Nowadays a lot of new ceramics are created and the optimized temperature program for their production is necessary. From one side, the process of ceramics firing must not be too fast, because the fast heating reduces the quality of the final product, e.g. it leads to the formation of holes, microcracks and deformations. From other side, ceramics sintering may not be too slow, because the slow firing requires much time and therefore high energy costs. The main task of sintering optimisation is to find the temperature program which ensures the production of high quality ceramics for the shortest time and the lowest energy costs. In order to solve the task of temperature optimization, it is necessary to know the exact physics and chemistry of the reactions taking place in green body during the firing. For example, we need to know temperatures, individual steps and reaction kinetics of both burnout of binder and shrinkage. Current work contains the example of kinetic modelling for firing of ceramics based on alumina, and using of this kinetic model for the optimization of firing process, including optimisation of burnout of binder based on TGA measurements and optimization of shrinkage based on dilatometer measurements. Result of this optimization reduced the firing time more than twice.