Method for growing beta-SiC nano fiber in situ in C/SiC composite material

Abstract

The invention provides a method for growing beta-SiC nano fiber in situ in a C / SiC composite material. The method comprises the followings steps of: (1) degumming carbon-fiber fabric in a tube furnace to remove epoxy resin glue on the surface; enabling the heating temperature to be 350-450 DEG C, insulating for 25-40min, and using nitrogen for protection; fully dissolving polycarbosilane in a solvent, and preparing polycarbosilane solution with the percentage concentration by weight being 30-40%; (2) adopting a vacuum impregnation method to impregnate the carbon-fiber fabric in the polycarbosilane solution; taking out the impregnated carbon-fiber fabric, drying in the air, curing for 1-3 hours at the temperature of 230-250 DEG C in the tube furnace; and (3) cracking the impregnated carbon-fiber fabric cured in the step (2) for 1-2 hours at the temperature of 1100-1400 DEG C to obtain a ceramic-based composite material. The method provided by the invention has the advantages that the SiC nano fiber is directly produced in situ in the process of preparing the composite material, and grows at a hole, uniform distribution of a precursor impregnant in the subsequent circulation is realized to a certain extent, the defect of the material is reduced, and the use performance of the composite material is improved. The method is simple in process, easy in control and convenient in operation.

Description

technical field [0001] The invention relates to the field of carbon fiber reinforced ceramic matrix composite materials, in particular to a method for in-situ growth of β-SiC nanofibers in C / SiC composite materials. Background technique [0002] Carbon fiber reinforced silicon carbide (C / SiC) composite material has significant advantages such as high temperature resistance, low density, high performance and oxidation resistance. High-tech fields such as high-speed trains, advanced missile weapons, and nuclear fusion energy have shown potential and huge application prospects. [0003] Carbon fibers have extremely high specific strength and specific modulus, excellent electrical and thermal conductivity, corrosion resistance, and good high temperature resistance in reducing atmospheres, and are widely used as reinforcing (toughening) phases of composite materials. However, in traditional C / C or C / SiC composites, no matter whether the carbon fiber in the felt is woven in 3D or...

AI Technical Summary

Problems solved by technology

However, the in situ generation of SiC nanofibers during the preparation of composites by the precursor impregnation pyrolysis method has not been reported yet.

Images