METHOD FOR OBTAINING A REFRACTORY MIXTURE CONTAINING BORON NITRIDE Russian patent published in 2022 - IPC C04B35/5835 C04B35/103 C04B35/65 

FIELD: refractory materials.

SUBSTANCE: invention relates to methods for producing refractory mixtures containing boron nitride and aluminum oxide, having a wide range of applications in blast furnace, steelmaking and foundry industries, in ferrous and non-ferrous metallurgy. A method is proposed for obtaining a refractory mixture containing boron nitride by processing an exothermic mixture containing boron oxide in the combustion mode in a nitrogen atmosphere. The exothermic mixture contains at least two powders, one of which consists of at least 95 wt. % of boron oxide and is contained in the mixture in an amount of 45-65 wt. % and the second is aluminum or an alloy of aluminum with silicon or magnesium, while the said exothermic mixture has porosity of 30 to 75%. The exothermic mixture is placed in an atmosphere of nitrogen gas at a pressure above 0.1 MPa, ignited, and an exothermic oxidation or nitriding reaction of aluminum is carried out in the mode of layered or volumetric combustion at a temperature of 1400-2200°C and a pressure of 1-30 MPa until the conversion of boron oxide into boron nitride, and the exothermic mixture into sintered material with a density of 1.5-2.9 g/cm³.

EFFECT: creation of a new waste–free method for producing a refractory mixture, which, with minimal energy consumption, makes it possible to obtain materials containing boron nitride.

8 cl, 1 tbl