A new method for preparation of TaC coating on C/C composite material is reported.The amorphous ethylate tantalum jellied as the precursor is prepared and spread densely on the surface of the C/C composite material so...A new method for preparation of TaC coating on C/C composite material is reported.The amorphous ethylate tantalum jellied as the precursor is prepared and spread densely on the surface of the C/C composite material so as to form a multilayer film.In a graphitization furnace the multilayer film is transformed into TaC coating at various temperatures.Ethylate tantalum film is characterized by FT-IR(Fourier transform infrared)spectra,XRD(X-ray diffraction)and SEM(scanning electron microscopy)and TaC coating is characterized by XRD and SEM.At 1200℃the coating contained TaC and Ta2O5,and at above 1400℃only TaC is formed.The coating formed at 1600℃is a continuous stratum structure,and that formed at 1600℃is a porous net structure.Analysis on thermodynamics and formation mechanism of TaC indicates that,after ethylate tantalum is decomposed,Ta2O5 is first produced and then transformed into Ta2C,and newly formed Ta2C is transformed into TaC by the sufficient C at last.展开更多
High-purity graphite is extensively utilized in the semiconductor industry.Enhancing its corrosion resistance is crucial for reducing the manufacturing costs of the third-generation semiconductors.In this study,a cont...High-purity graphite is extensively utilized in the semiconductor industry.Enhancing its corrosion resistance is crucial for reducing the manufacturing costs of the third-generation semiconductors.In this study,a continuous and dense TaC coating was fabricated on the surface of graphite using CVD method.The corrosion resistance and mechanism of the coating were investigated in a high-temperature steam environment.This environment involved temperatures exceeding 2200 K and the erosion of the coating by Si-containing mixed steam flows.The results indicated that the corrosion in the affected areas was primarily due to chemical reactions,characterized by the formation of pores and micro-cracks,whereas failure areas were dominated by mechanical delamination,which led to macroscopic defects.Moreover,the mixed high-temperature steam corrosion of the TaC coating showed preferential selectivity,resulting in a stepped corrosion morphology at the crystalline level.The surface roughness of the samples significantly increased after corrosion,from 0.36 to 5.28μm,although the surface composition remained largely unchanged.The TaC coating provides a certain level of protection to the graphite substrate,enhancing the service life of graphite components and demonstrating promising application potential.展开更多
文摘A new method for preparation of TaC coating on C/C composite material is reported.The amorphous ethylate tantalum jellied as the precursor is prepared and spread densely on the surface of the C/C composite material so as to form a multilayer film.In a graphitization furnace the multilayer film is transformed into TaC coating at various temperatures.Ethylate tantalum film is characterized by FT-IR(Fourier transform infrared)spectra,XRD(X-ray diffraction)and SEM(scanning electron microscopy)and TaC coating is characterized by XRD and SEM.At 1200℃the coating contained TaC and Ta2O5,and at above 1400℃only TaC is formed.The coating formed at 1600℃is a continuous stratum structure,and that formed at 1600℃is a porous net structure.Analysis on thermodynamics and formation mechanism of TaC indicates that,after ethylate tantalum is decomposed,Ta2O5 is first produced and then transformed into Ta2C,and newly formed Ta2C is transformed into TaC by the sufficient C at last.
文摘High-purity graphite is extensively utilized in the semiconductor industry.Enhancing its corrosion resistance is crucial for reducing the manufacturing costs of the third-generation semiconductors.In this study,a continuous and dense TaC coating was fabricated on the surface of graphite using CVD method.The corrosion resistance and mechanism of the coating were investigated in a high-temperature steam environment.This environment involved temperatures exceeding 2200 K and the erosion of the coating by Si-containing mixed steam flows.The results indicated that the corrosion in the affected areas was primarily due to chemical reactions,characterized by the formation of pores and micro-cracks,whereas failure areas were dominated by mechanical delamination,which led to macroscopic defects.Moreover,the mixed high-temperature steam corrosion of the TaC coating showed preferential selectivity,resulting in a stepped corrosion morphology at the crystalline level.The surface roughness of the samples significantly increased after corrosion,from 0.36 to 5.28μm,although the surface composition remained largely unchanged.The TaC coating provides a certain level of protection to the graphite substrate,enhancing the service life of graphite components and demonstrating promising application potential.
