Graded Baking as a Method for Homogenizing the Structure of Dense Ceramics

The possibility of improvement of technological properties of ceramic mass through optimization of its composition is investigated. For a ceramic mixture consisting of 60% montmorillonite containing clay and 40 wt % kaolinite containing clay, a simple geometrical roasting process is simulated which provides minimum temperature gradients between surfaces and middle layers of samples. To obtain samples with a uniform structure in volume, graded baking is developed at temperatures of 600, 700, 800, 900, and 1000°C with sequential holding for 1 h at heating rates of 5 and 25 K/min. Experimental results of the evaluation of the influence of the heating rate on the kinetics of change in the macro parameters of samples are given. Disclosed are methods of controlling structural changes in high-temperature baking. It is shown that the graded baking of the optimized ceramic mixture allows expanding the sintering interval, and the variation in the heating rate contributes to homogenization of the structure of the dense ceramic.