The sinter plate is a tool used to carry and transport the fired ceramic embryo in a ceramic kiln. It is mainly used in the ceramic kiln as a carrier for bearing, heat insulation and conveying the burned ceramics. Through it, it can improve the heat conduction velocity of the sintering plate, make the sintering products evenly heated, effectively reduce energy consumption and speed up the firing speed, improve the output, so that the same kiln fired products colorless difference and other advantages.
Corundum mullite material has high thermal shock resistance and high temperature strength, and good chemical stability and wear resistance. Therefore, it can be used repeatedly at higher temperatures, especially for sintered magnetic cores, ceramic capacitors and insulating ceramics.
Sintering products are laminated sintering products. Each layer of sintering plate plus product weight is about 1kg, generally l0 layer, so sintering plate may bear the maximum pressure of more than ten kilograms. At the same time, to bear the thrust when moving and the friction of loading and unloading products, but also many cold and hot cycles, therefore, the use of the environment is very harsh.
Without considering the interaction of the three factors, alumina powder, kaolin and calcination temperature all affect thermal shock resistance and creep. The thermal shock resistance increases with the addition of alumina powder, and it decreases with the increase of firing temperature. When kaolin content is 8%, the thermal shock resistance is the lowest, followed by kaolin content of 9.5%. The creep decreases with the addition of alumina powder, and the creep is the lowest when the content of kaolin is 8%. The creep is maximum at 1580℃. In order to give consideration to the thermal shock resistance and creep resistance of the materials, the best results are obtained when the alumina content is 26%, kaolin is 6.5% and calcination temperature is 1580℃.
There is a certain gap between corundum-mullite particles and matrix. And there are some cracks around the particles, which is caused by the mismatch of thermal expansion coefficient and elastic modulus between particles and matrix, resulting in microcracks in the products. When the expansion coefficient of particles and matrix does not match, the aggregate and matrix are easy to separate when heated or cooled. A gap layer is formed between them, resulting in the appearance of microcracks. The existence of these micro-cracks will lead to the degradation of mechanical properties of the material, but when the material is subjected to thermal shock. In the gap between aggregate and matrix, it can play the role of buffer zone, which can absorb certain stress and avoid the stress concentration at the crack tip. At the same time, the thermal shock cracks in the matrix will stop at the gap between the particles and the matrix, which can prevent the crack propagation. Thus, the thermal shock resistance of the material is improved.
Post time: Apr-08-2022