METHOD FOR PRODUCING NON-CORING SILICON CARBIDE FIBER OF β-MODIFICATION Russian patent published in 2021 - IPC D01D5/88 

FIELD: chemical industry.

SUBSTANCE: invention relates to the field of chemical industry, namely, to a method for producing a non-coring silicon carbide fiber of β-modification. Non-coring silicon carbide fibers can be used in nuclear power, aerospace engineering, and other high-tech industries. The method includes four stages. At the first stage, a multi-filamentous polymer fiber is formed by extrusion from a polycarbosilane melt (hereinafter – PCS). To do this, the PCS is introduced into the extruder and the PCS is heated to the optimal molding temperature to obtain its homogeneous melt. The PCS melt is squeezed out through the spinneret at a pressure of 1.5-4.0 MPa to form a polymer fiber. It is gradually cooled in an inert atmosphere to room temperature, followed by curing. At the second stage, thermal-oxidative crosslinking is performed. At the third stage, carbonization of the resulting cured polymer fiber is carried out with its transfer to the ceramic phase. At the fourth stage, the resulting silicon carbide fiber of β-modification is dressed.

EFFECT: provided are possibility of obtaining continuous non-coring silicon carbide fibers, increasing their strength characteristics, increasing resistance to high temperatures and high creep resistance, stability of fiber properties, optimal average fiber diameter, and the absence of foreign impurities in the fiber composition.

8 cl, 31 dwg, 3 tbl, 3 ex