Over the past years, great achievements have been made in the development of coating technologies for surface improvement of aluminum alloys. Despite these achievements, the role in the market strongly depends on the ...Over the past years, great achievements have been made in the development of coating technologies for surface improvement of aluminum alloys. Despite these achievements, the role in the market strongly depends on the ability of surface coating technology under technical and economic considerations to meet the increased demands for heavy tribological applications of aluminum alloys. Microplasma oxidation (MPO) technology has recently been studied as a novel and effective means to provide thick and hard ceramic coating with improved properties such as excellent load-bearing and wear resistance properties on aluminum alloys. The present work covers the evaluation of the performances of current single and duplex coatings combining MPO, physical vapor deposition (PVD), and plasma assisted chemical vapor deposition (PACVD) coatings on aluminum alloys. It suggests that the MPO coating is a promising candidate for design engineers to apply aluminum alloys to heavy load-bearing applications. The prospective future for the research on MPO coatings is introduced as well.展开更多
Carbon nanosheet films were deposited on A1 substrates by using plasma assisted chemical vapor deposition （PACVD） technique. And after being peeled off from A1 substrates, carbon nanosheet powders （CNSPs） were obt...Carbon nanosheet films were deposited on A1 substrates by using plasma assisted chemical vapor deposition （PACVD） technique. And after being peeled off from A1 substrates, carbon nanosheet powders （CNSPs） were obtained. In Raman spectrum of carbon film, there was a strong and broadened peak at about 1,580 cm^-1, indicating a carbon diamond-like film. Atomic force microscope image showed that the carbon diamond-like film had a grain size less than 100 nm, and its surface roughness Ra was 17.95 nm in an area of 5×5 μm^2. The CNSPs were irregular sheets with curly edges and a length of several micrometers to several hundreds of micrometers. The BET surface area of CNSPs was 6.66 m^2/g with no micro-pore present, which was confirmed by N2 adsorption-desorption characterization. In the adsorption testing, when the relative pressure p/po was higher than 0.3, the adsorption behavior did not follow the Langmuir equation. The addition of CNSPs to carbon black （catalyst support） could improve hydrodesulfurization performance of carbon supported Ni-W catalysts for diesel oil.展开更多
文摘Over the past years, great achievements have been made in the development of coating technologies for surface improvement of aluminum alloys. Despite these achievements, the role in the market strongly depends on the ability of surface coating technology under technical and economic considerations to meet the increased demands for heavy tribological applications of aluminum alloys. Microplasma oxidation (MPO) technology has recently been studied as a novel and effective means to provide thick and hard ceramic coating with improved properties such as excellent load-bearing and wear resistance properties on aluminum alloys. The present work covers the evaluation of the performances of current single and duplex coatings combining MPO, physical vapor deposition (PVD), and plasma assisted chemical vapor deposition (PACVD) coatings on aluminum alloys. It suggests that the MPO coating is a promising candidate for design engineers to apply aluminum alloys to heavy load-bearing applications. The prospective future for the research on MPO coatings is introduced as well.
基金the Venture Fund of PetroChina Company Limted (050511-3-4)
文摘Carbon nanosheet films were deposited on A1 substrates by using plasma assisted chemical vapor deposition （PACVD） technique. And after being peeled off from A1 substrates, carbon nanosheet powders （CNSPs） were obtained. In Raman spectrum of carbon film, there was a strong and broadened peak at about 1,580 cm^-1, indicating a carbon diamond-like film. Atomic force microscope image showed that the carbon diamond-like film had a grain size less than 100 nm, and its surface roughness Ra was 17.95 nm in an area of 5×5 μm^2. The CNSPs were irregular sheets with curly edges and a length of several micrometers to several hundreds of micrometers. The BET surface area of CNSPs was 6.66 m^2/g with no micro-pore present, which was confirmed by N2 adsorption-desorption characterization. In the adsorption testing, when the relative pressure p/po was higher than 0.3, the adsorption behavior did not follow the Langmuir equation. The addition of CNSPs to carbon black （catalyst support） could improve hydrodesulfurization performance of carbon supported Ni-W catalysts for diesel oil.
