Effect Of Silicon Carbide Coating On Tensile Properties Of Carbon Fiber Monofilament

Carbon fiber has high specific strength,high specific modulus and other excellent performance,so often been used as a reinforcement of composite.But existing a series of interface problems between carbon fibers and the substrate,such as interface compatibility is poor,the binding force is weak,et al.which makes the performance of the composite materials decreased.Therefore,the carbon fiber surface treatment is necessary.In recent years,the method of improving the interface between carbon fiber and matrix by coating silicon carbide on the surface of carbon fiber has been more mature.However,the effect of silicon carbide coating on the tensile properties of carbon fiber is rarely studied.In this studied,using of method in situ gas-solid reaction prepared SiC coating on the carbon fiber.The effect of silicon carbide coating on the tensile properties of monofilament carbon fiber was studied.The result showed:1.Let silicon vapor and itself carbon of the carbon fiber formed silicon carbide layer deposition on the surface of carbon fiber with the deposition temperature was1450 ? keeping 3 h.SEM analysis showed that,when the thickness of silicon carbide coating reaches 0.15 ?m,the prepared SiC coating is completely covered and compacted on the carbon fiber surface.Tensile tests were carried out on carbon fiber monofilaments deposited SiC coatings,it was found that with the increase of the thickness of silicon carbide coating,the tensile strength and the elongation remains essentially unchanged,apparent elastic modulus of monofilament carbon fiber show an increasing trend,.2.Let C₃H₈ decomposed formed pyrolytic carbon layer deposition on the surface of carbon fiber with the deposition temperature was 950 ?,SEM analysis showed that,the thickness of the pyrolytic carbon layer can reach 1?m after deposition for 0.5 h,and the coating thickness is about 2 ?m after 2 h.Tensile tests were carried out on monofilaments carbon fiber deposited the pyrolytic carbon layer,it was found that with the increase of the thickness of pyrolytic carbon coating,the apparent elastic modulus of monofilament carbon fiber is almost constant,and the elongation and tensile strength are reduced.3.Let silicon vapor and pyrolytic carbon?PyC?on the surface of the carbon fiber formed silicon carbide layer deposition on the surface of carbon fiber with the deposition temperature was 1450 ? keeping 3 h.Tensile tests were carried out onmonofilaments carbon fiber deposited the PyC-SiC layer.It was found that the thickness of PyC-SiC layer is less than 1.1 ?m,the tensile strength and elongation of monofilament carbon fiber are almost constant,and the apparent elastic modulus decreases,When the thickness of PyC-SiC layer is more than 1.1 ?m,the tensile strength of monofilament carbon fiber are reduced and the apparent elastic modulus increases,the elongation of monofilament carbon fiber remains essentially unchanged.