METHOD FOR OBTAINING COMPOSITE CERAMICS BASED ON SILICON NITRIDE Russian patent published in 2018 - IPC C04B35/596 B29C47/02 B29C64/106 

FIELD: technological processes.

SUBSTANCE: invention relates to the production of composite ceramic products and can be used in construction or industry, in particular in thermally loaded areas of power plants. In accordance with the claimed method for producing articles based on silicon nitride, a matrix dispersion based on paraffin and silicon nitride is prepared, it is heated to its liquid phase, long fiber of silicon compounds is waxed, then intermediate products of a predetermined shape and with predetermined strength properties are produced using a universal printing unit, providing the necessary geometric connection of the matrix and fibers by means of a pultrusion injection nozzle. During the process of producing intermediate products, using the universal printing unit, the angle of the inclination of the fiber is changed in accordance with the task, both from layer to layer and within one layer, providing controlled layer-by-layer modeling of the intermediate products. After they have been cooled, paraffin is removed from the intermediate products by a two-stage calcination process, first in an adsorbent with heating up to 200 °C, and then in air with heating up to 600 °C, after which they are placed in a sealed oven and reactive sintering of silicon nitride at a temperature of up to 1,400 °C and nitrogen pressure up to 0.5 atm is performed.

EFFECT: ensuring the possibility of efficient modeling in the production of composite products with the required physical and technical properties.

1 cl, 1 dwg