Research On Corrosion Resistance And Thermal Shock Resistance Of Carbon-silicon Fiber

Silicon carbide ceramic fiber with its excellent oxidation resistance, hightemperature resistance, corrosion resistance and resistance to radiation properties, iswidely used in aviation, machinery, war industry, energy and other fields, and, it hasgood compatibility with metals, ceramics and polymers, which is made one of the highperformance reinforced fiber material first by advanced composite material and has avery broad prospect of application.This paper adopted silicon carbide ceramic fiber as experimental material,which ismanufactured by using pioneer body reforming process by a company of Suzhou City.Through the test of corrosion resistance and thermal shock resistance, the measurementand analysis of the mechanical properties of the fiber and fiber structure before and afterprocessing, systematically discussed each experimental parameters, such as thecorrosion time, concentration and temperature, which silicon carbide ceramic fiberunder the conditions of acid, alkali and salt medium, to the influence of silicon carbideceramic fiber. At the same time, with the help of many kinds of characterizationmethods and test method, such as X-ray diffraction analysis, electronic scanningelectron microscopy analysis and the electronic energy analysis, infrared spectrometryanalysis, thermogravimetric analysis and mechanics performance test and so on,penetratingly systematically researching the mechanism of silicon carbide ceramicfiber’s corrosion resistance and thermal shock resistance.The study results show that, in the solution of H₂SO₄, NaOH and Na₂SO₄, as thecorrosion time, corrosion solution concentration and corrosion solution temperaturecontinuously increasing, silicon carbide ceramic fibers are gradually rotted andmechanical properties are gradually declining, because of silicon carbide ceramic fibers contains solid alumina and fiber surface has a protective layer of silicon dioxideoxidation film was "chemical corrosion" result in a particular case. Therefore, producethe high performance chemically resistant silicon carbide ceramic fiber, should doesn’tcontain or contain very small amount impurities,which can response with acid, alkaliand salt, meanwhile, should reduce the oxidation of oxygen on itself as far as possibleduring silicon carbide ceramic fiber production process.Thorough the measurement and analysis of the mechanical properties and the fibersurface morphology of the silicon carbide ceramic fiber, the paper research the thermalshock resistance of silicon ceramic fiber material. The study results show that, largesilicon carbide particles affected the crack growth, adjusted the stress distribution underhigh temperature, and improved the thermal shock resistance of the silicon ceramic fibermaterial; the thermal shock resistance of the ceramic material depended on its thermalexpansion, low thermal expansion materials have an outstanding performance at theaspect of its thermal shock, therefore, if it does not affect other performances of thesilicon ceramic fiber, join the second phase can change its thermal expansion to improveits thermal shock resistance.