Method to develop structural ceramic material. RU patent 2450998.

FIELD: construction.

SUBSTANCE: charge is prepared, containing the following components, mol. %: SiC - 53-62, BN - 3-7, Al - 35-40, at the same time the rated quantity of aluminium is introduced in it in full volume, doing mechanical activation. Primary stocks are shaped from the charge, dried, exposed to vacuum sintering and grinding. After the secondary shaping the stocks are dried, sintered in vacuum, nitrified at the temperature of 1050°C, and thermal treatment is carried out at 1400°C. Vacuum sintering is carried out at the temperature of 1150±2°C. The produced structural ceramic material is characterised by higher density and strength: withstands compression stress of at least 450 MPa, bending stress - of at least 130 MPa at high working temperatures of the material (at least 1400°C). Shrinkage at the stage of cermet conversion into ceramics - not more than 0.5%.

EFFECT: reduced shrinkage.

IPC classes for russian patent Method to develop structural ceramic material. RU patent 2450998. (RU 2450998):

C04B35/65 - Reaction sintering of free metal- or free silicon-containing compositions

C04B35/581 -

C04B35/573 -

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