METHOD OF HARDENING CARBON FIBRES Russian patent published in 2017 - IPC D01F9/12 D01F11/16 

FIELD: chemistry.

SUBSTANCE: invention relates to hardening of carbon fibres (CF) used to produce composite materials. The method of hardening carbon fibres includes heat treatment with the drawing of fibres through a heating zone. Heat treatment is carried out in the high-temperature heating zone of 2500-3000°C, in an inert atmosphere, for 18-32 seconds, with a load applied to the treated fibre in the range of 1.0 to 3.75 g/tex due to the difference in the speeds of the feeding and receiving mechanisms. The load on the fibre being treated is inversely proportional to the residence time in the high-temperature heating zone. In addition, additional impregnation of hydrocarbons with an aprotic composition of an aqueous solution of polyvinyl alcohol of 6-8 g/liter and drying in a quartz tube furnace can be carried out, with an increase in temperature, depending on the residence time in the drying zone from 60 to 120 seconds in the range of 130-300°C.

EFFECT: invention makes it possible to produce carbon fibre with an increased value of ultimate tensile strength and an increased value of the elasticity module.

2 cl, 8 dwg, 3 tbl