The friction and wear properties of amorphous carbon nitride(a-CN x)coatings in water lubrication were reviewed.The influences of mating materials and tribological variables such as normal load(W)and sliding speed(V)o...The friction and wear properties of amorphous carbon nitride(a-CN x)coatings in water lubrication were reviewed.The influences of mating materials and tribological variables such as normal load(W)and sliding speed(V)on the friction and wear properties of the a-CN x coatings were analyzed.It was indicated that the specific wear rate of the a-CN x coatings was related to the hydration reaction of mating materials with water.If the mating materials were easily hydrated,the specific wear rate of a-CN x coatings was low.The water-lubricated properties of the a-CN x coatings were better in comparison to the a-C coatings.The a-CN x/Si-based non-oxide ceramics tribo-pairs exhibited the lowest friction coefficient and wear rate.To describe their friction and wear properties at the normal loads of 3—15Nand the sliding speeds of 0.05—0.5m/s,the wear-mechanism maps for the a-CN x/SiC(Si3N4)tribo-pairs in water were developed.展开更多
Raman spectra of amorphous carbon nitride films (a-C:N) resemble those of typical amorphous carbon (a-C), and no specific features in the spectra are shown due to N doping. The present work provides a correlation...Raman spectra of amorphous carbon nitride films (a-C:N) resemble those of typical amorphous carbon (a-C), and no specific features in the spectra are shown due to N doping. The present work provides a correlation between the microstructure and vibrational properties of a-C:N films from first principles. The six periodic model structures of 64 atoms with various mass densities and nitrogen contents are generated by the liquid-quench method using Car-Parinello molecular dynamics. By using Raman coupling tensors calculated with the finite electric field method, Raman spectra are obtained. The calculated results show that the vibrations of C=N could directly contribute to the Raman spectrum. The similarity of the Raman line shapes of N-doped and N-free amorphous carbons is due to the overlapping of C=N and C=C vibration bands. In addition, the origin of characteristic Raman peaks is also given.展开更多
Hydrogenated amorphous carbon nitride (a-CN<sub>x</sub>:H) films were formed on Al films deposited on Si or glass (SiO<sub>2</sub>) substrates, using pulsed radio frequency (PRF) supermagnetron...Hydrogenated amorphous carbon nitride (a-CN<sub>x</sub>:H) films were formed on Al films deposited on Si or glass (SiO<sub>2</sub>) substrates, using pulsed radio frequency (PRF) supermagnetron plasma (SMP) chemical vapor deposition (CVD) with N<sub>2</sub>/i-C<sub>4</sub>H<sub>10</sub> mixed gases. a-CN<sub>x</sub>:H films were grown under the upper and lower electrode RF powers (13.56 MHz) of continuous and pulsed conditions, respectively, which showed low band gap of about 0.7 eV. a-CN<sub>x</sub>:H films deposited on the Al/Si or Al/SiO<sub>2</sub> substrates showed same low threshold emission electric field (ETH) of 12 V/μm. Multiple layer of Al or ITO (anode)/50nm-SiO<sub>2</sub>/a-CN<sub>x</sub>:H/Al (cathode)/Si structures showed Fowler-Nordheim (FN) electron tunneling effect in both forward and reverse current directions. 12.5 nm a-CN<sub>x</sub>:H film on p-Si substrate showed a photoelectric conversion. Energy band structure and electron conduction models were proposed for the active states of both the field emission and FN tunneling devices and photovoltaic cells.展开更多
基金Supported by the National Natural Science Foundation of China(50675102,50975137,51375231)the Program for New Century Excellent Talents in University(NCET-10-068)+2 种基金the Research Fund for the Doctoral Program of Higher Education(20133218110030)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Japan Society for the Promotion of Science under Grant-in-Aid for Scientific Research(JSPS Fellows P03219)
文摘The friction and wear properties of amorphous carbon nitride(a-CN x)coatings in water lubrication were reviewed.The influences of mating materials and tribological variables such as normal load(W)and sliding speed(V)on the friction and wear properties of the a-CN x coatings were analyzed.It was indicated that the specific wear rate of the a-CN x coatings was related to the hydration reaction of mating materials with water.If the mating materials were easily hydrated,the specific wear rate of a-CN x coatings was low.The water-lubricated properties of the a-CN x coatings were better in comparison to the a-C coatings.The a-CN x/Si-based non-oxide ceramics tribo-pairs exhibited the lowest friction coefficient and wear rate.To describe their friction and wear properties at the normal loads of 3—15Nand the sliding speeds of 0.05—0.5m/s,the wear-mechanism maps for the a-CN x/SiC(Si3N4)tribo-pairs in water were developed.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11074061 and 50972031)the Natural Science Foundation for Youth of Heilongjiang Province of China (Grant No. QC2010006)+1 种基金the Science and Technology Plan of Heilongjiang Provincial Education Department, China (Grant No. 12511163)the Foundation for Young Key Scholars of Harbin Normal University, China (Grant No. 11KXQ-08)
文摘Raman spectra of amorphous carbon nitride films (a-C:N) resemble those of typical amorphous carbon (a-C), and no specific features in the spectra are shown due to N doping. The present work provides a correlation between the microstructure and vibrational properties of a-C:N films from first principles. The six periodic model structures of 64 atoms with various mass densities and nitrogen contents are generated by the liquid-quench method using Car-Parinello molecular dynamics. By using Raman coupling tensors calculated with the finite electric field method, Raman spectra are obtained. The calculated results show that the vibrations of C=N could directly contribute to the Raman spectrum. The similarity of the Raman line shapes of N-doped and N-free amorphous carbons is due to the overlapping of C=N and C=C vibration bands. In addition, the origin of characteristic Raman peaks is also given.
文摘Hydrogenated amorphous carbon nitride (a-CN<sub>x</sub>:H) films were formed on Al films deposited on Si or glass (SiO<sub>2</sub>) substrates, using pulsed radio frequency (PRF) supermagnetron plasma (SMP) chemical vapor deposition (CVD) with N<sub>2</sub>/i-C<sub>4</sub>H<sub>10</sub> mixed gases. a-CN<sub>x</sub>:H films were grown under the upper and lower electrode RF powers (13.56 MHz) of continuous and pulsed conditions, respectively, which showed low band gap of about 0.7 eV. a-CN<sub>x</sub>:H films deposited on the Al/Si or Al/SiO<sub>2</sub> substrates showed same low threshold emission electric field (ETH) of 12 V/μm. Multiple layer of Al or ITO (anode)/50nm-SiO<sub>2</sub>/a-CN<sub>x</sub>:H/Al (cathode)/Si structures showed Fowler-Nordheim (FN) electron tunneling effect in both forward and reverse current directions. 12.5 nm a-CN<sub>x</sub>:H film on p-Si substrate showed a photoelectric conversion. Energy band structure and electron conduction models were proposed for the active states of both the field emission and FN tunneling devices and photovoltaic cells.