METHOD OF MANUFACTURING LAYERED CERAMIC PRODUCTS FROM COMPOSITE MATERIAL Russian patent published in 1998 - IPC

FIELD: ceramics. SUBSTANCE: invention relates to production of refractory ceramics, chiefly structural-destination ceramics, and can find use when manufacturing layered ceramic products, for example, over-rotor seals, press molds for molding articles from heat-resistant glass, armor plates, etc. In order to diversify properties of manufactured products, layered structures are made from Si₃N₄-BN composite material all properties of which vary when initial component makeup is varied. For that, ceramic charge with at least two different makeups is prepared containing silicon nitride- yttrium oxide or silicon nitride-magnesium oxide and boron nitride composition with different component ratios. Charge is preliminarily compressed on mechanical press in metallic press molds into briquets composed of silicon nitride-based charge with gradual variation of boron nitride content to 50%. Number of briquets and sequence of their laying are determined by specific property range, whereas hot pressing is carried out at 1550-1700 C at pressure 10-20 MPa under nitrogen atmosphere for 2-3 h. EFFECT: diversified properties of ceramic products. 4 cl, 5 dwg