Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) ...Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film(3.73×10-8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.展开更多
Diesel particulate matter(DPF) is usually employed to meet the stringent regulations on particulate matter(PM) emissions for diesel engine. To resolve the DPF regeneration problem, comprehensive information about the ...Diesel particulate matter(DPF) is usually employed to meet the stringent regulations on particulate matter(PM) emissions for diesel engine. To resolve the DPF regeneration problem, comprehensive information about the factors influencing PM oxidation behaviors must be understood. Large amounts of factors related to PM oxidation activity have been investigated, however, some relations are still ambiguous. This paper reviews the factors related to PM oxidation activity that the factors are divided into the engine-correlated and engine-uncorrelated factors. The methods with both advantages and disadvantages to test the oxidation behaviors are introduced. The microstructure and ingredient being fundamental factors affecting PM oxidation behaviors are as the principle line to correlate PM oxidation behaviors and engine-correlated factors. The relations of engine-correlated factors with oxidation behaviors are obtained though advanced technologies that are mutual complementation. The engine-uncorrelated factors are also reviewed that these factors are vital to oxidation activity changes. Multiple-factor analysis rather than single-factor analysis should be developed to make the oxidation behaviors of diesel PM more clear.展开更多
基金国家重点基础研究发展规划(973)(the National Grand Fundamental Research 973 Program of China under Grant No.2002CB3122000)国家高技术研究发展计划(863)(the National High-Tech Research and Development Plan of China under Grant No.20060104Z1081)+2 种基金上海市自然科学基金(the Natural Science Foundation of Shanghai of China under Grant No.05ZR14038)国家杰出青年科学基金(the National Science Fund of China for Distinguished Young Scholar under Grant No.60625302)上海市科委重大基础研究基金(No.05DJ14002)。
基金Project(51271012)supported by the National Natural Science Foundation of China
文摘Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film(3.73×10-8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.
基金support by the Science and Technology Planning Project of Hebei Province,China(Grant No.15273703D)
文摘Diesel particulate matter(DPF) is usually employed to meet the stringent regulations on particulate matter(PM) emissions for diesel engine. To resolve the DPF regeneration problem, comprehensive information about the factors influencing PM oxidation behaviors must be understood. Large amounts of factors related to PM oxidation activity have been investigated, however, some relations are still ambiguous. This paper reviews the factors related to PM oxidation activity that the factors are divided into the engine-correlated and engine-uncorrelated factors. The methods with both advantages and disadvantages to test the oxidation behaviors are introduced. The microstructure and ingredient being fundamental factors affecting PM oxidation behaviors are as the principle line to correlate PM oxidation behaviors and engine-correlated factors. The relations of engine-correlated factors with oxidation behaviors are obtained though advanced technologies that are mutual complementation. The engine-uncorrelated factors are also reviewed that these factors are vital to oxidation activity changes. Multiple-factor analysis rather than single-factor analysis should be developed to make the oxidation behaviors of diesel PM more clear.