An overview of science and technology of pretreatment process suitable for automotive finishing with cathodic electrodeposition primer is presented in details in this paper. Both the theoretical principles and practic...An overview of science and technology of pretreatment process suitable for automotive finishing with cathodic electrodeposition primer is presented in details in this paper. Both the theoretical principles and practical aspects of tricationic phosphating process that are used in automotive industry are discussed in details. The characteristic features of phosphate coatings of both conventional high zinc phosphating formulations and modern tricationic phosphating formulations on steel surface are compared in details by SEM, EDX and XRD techniques. The corrosion protection of the phosphated and painted steel panels were evaluated by both salt spray test and electrochemical impedance spectroscopy (EIS). The analysis of impedance data in terms of pore resistance (Rpo), coating capacitance (Cc) and breakpoint frequency (fb) as a function of salt spray exposure time provides a clear insight into the mechanism of superior corrosion resistance provided by the modern tricationic phosphating formulations compared with conventional high zinc phosphating formulations.展开更多
More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties...More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys still are the main research focus.Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Significant contributions to the research and development of magnesium alloys were made by Chongqing University,Shanghai Jiaotong University,and Chinese Academy of Sciences in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the United States,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,etc..This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2021.Based on the issues and challenges identified here,some future research directions are suggested.展开更多
More than 4600 papers in the field of Mg and Mg alloys were published and indexed in the Web of Science(WoS)Core Collection database in 2022.The bibliometric analyses indicate that the microstructure,mechanical proper...More than 4600 papers in the field of Mg and Mg alloys were published and indexed in the Web of Science(WoS)Core Collection database in 2022.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys are still the main research focus.Bio-Mg materials,Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Notable contributions to the research and development of magnesium alloys were made by Chongqing University(>200 papers),Chinese Academy of Sciences,Shanghai Jiao Tong University,and Northeastern University(>100 papers)in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the USA,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,and National University of Singapore in Singapore,etc.This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2022.Based on the issues and challenges identified here,some future research directions are suggested.展开更多
This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface pr...This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface preparation, coating application, as well as coating inspection for four types of major production facilities.展开更多
In order to solve the problems related with processing low-quality Liaohe highly sour crude, the Liaohe Petrochemical Company has explored the possibility in optimizing the processing of highly sour crude by adopting ...In order to solve the problems related with processing low-quality Liaohe highly sour crude, the Liaohe Petrochemical Company has explored the possibility in optimizing the processing of highly sour crude by adopting different process schemes depending upon the properties of the highly sour crude. The Liaohe naphthenic-base crude oil with low freezing point is earmarked for manufacture of naphthenic lube oils and heavy traffic paving asphalt, while the extra-heavy Liaohe crude with high acid number is routed directly to delayed coking unit coupled with corresponding corrosion preventing measures, resulting in tackling the problem of equipment corrosion arising from refining of Liaohe highly sour crude to obtain light distillates from Liaohe heavy crude through a short process scheme.展开更多
The corrosion resistance of NiCrBSi coating deposited on steel substrate by HVOF was examined using electrochemical tests and immersion tests so as to offer an experimental basis to expand a promising applied field of...The corrosion resistance of NiCrBSi coating deposited on steel substrate by HVOF was examined using electrochemical tests and immersion tests so as to offer an experimental basis to expand a promising applied field of HVOF in aqueous medium, comparing with those of coatings deposited by oxyacetylene flame spraying and flame cladding. The results show that the general corrosion rate of HVOF sprayed coatings is quite bigger than that of clad coatings, but it is less sensitive to local corrosion. There is less and smaller porosity in the coatings deposited by HVOF than that in flame sprayed coatings. The effects of porosity on the corrosion current density was indistinctive, but the existence of large amount of defects in the coatings damaged the cohesion of the coatings, causing the metallic particles drop off from the coatings under the influence of corrosive medium. Improving the quality and reducing the porosity of coatings is the key to get the coatings with high corrosion resistance.展开更多
Carbonyl iron(CI)particles as magnetic microwave absorption material often suffer from serious corrosion under corrosive environment which leads to performance deterioration.In this study,fluorin-containing acrylate t...Carbonyl iron(CI)particles as magnetic microwave absorption material often suffer from serious corrosion under corrosive environment which leads to performance deterioration.In this study,fluorin-containing acrylate type polymer network layers with thickness ranging from tens of nanometers to around one hundred nanometers were formed continuously around CI.The crosslinked coating layer(named FT)effectively increases CI’s thermal decomposition temperature by at least 34%.The FT-coated CI(named CI-FT)was able to resist both inorganic and organic corrosive media attacking efficiently compared with bare CI.The surface polymer network could also help CI withstand organic medium dissolution which proved the firmness of coating.Cyclic voltammetry(CV)test revealed that the coating layer could significantly reduce maximum oxidation current density of CI by more than 45 times.Tafel polarization study during CV tests also confirmed that thicker FT coating layer could help CI sample stabilize corrosion current density.Meanwhile,the surface coating also enhanced the impedance matching properties of CI as microwave absorber and the CI-FT samples demonstrated improved microwave absorption properties which degenerated little after corrosive medium soaking compared with that of CI.展开更多
文摘An overview of science and technology of pretreatment process suitable for automotive finishing with cathodic electrodeposition primer is presented in details in this paper. Both the theoretical principles and practical aspects of tricationic phosphating process that are used in automotive industry are discussed in details. The characteristic features of phosphate coatings of both conventional high zinc phosphating formulations and modern tricationic phosphating formulations on steel surface are compared in details by SEM, EDX and XRD techniques. The corrosion protection of the phosphated and painted steel panels were evaluated by both salt spray test and electrochemical impedance spectroscopy (EIS). The analysis of impedance data in terms of pore resistance (Rpo), coating capacitance (Cc) and breakpoint frequency (fb) as a function of salt spray exposure time provides a clear insight into the mechanism of superior corrosion resistance provided by the modern tricationic phosphating formulations compared with conventional high zinc phosphating formulations.
基金support from the Guangdong Major Project of Basic and Applied Basic Research(2020B0301030006)National Natural Science Foundation of China(NSFC)(No.52071036)+1 种基金Key Research and Development Program of Zhejiang Province(No.2021C01086)the Fundamental Research Funds for the Central Universities Project(Nos.2021CDJCGJ009,SKLMT-ZZKT-2021M11)is also gratefully acknowledged.
文摘More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys still are the main research focus.Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Significant contributions to the research and development of magnesium alloys were made by Chongqing University,Shanghai Jiaotong University,and Chinese Academy of Sciences in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the United States,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,etc..This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2021.Based on the issues and challenges identified here,some future research directions are suggested.
基金This work was financially supported by the National Key Research and Development Program of China(No.2021YFB3701100)the National Natural Science Foundation of China(Nos.52171104 and U20A20234)+1 种基金the Chongqing Research Program of Basic Research and Frontier Technology,China(Nos.cstc2021ycjh-bgzxm0086 and 2019jcyj-msxmX0306)the fundamental Research funds for Central Universities,China(Nos.SKLMT-ZZKT-2022R04,2021CDJJMRH-001,and SKLMT-ZZKT-2022M12).
文摘More than 4600 papers in the field of Mg and Mg alloys were published and indexed in the Web of Science(WoS)Core Collection database in 2022.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys are still the main research focus.Bio-Mg materials,Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Notable contributions to the research and development of magnesium alloys were made by Chongqing University(>200 papers),Chinese Academy of Sciences,Shanghai Jiao Tong University,and Northeastern University(>100 papers)in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the USA,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,and National University of Singapore in Singapore,etc.This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2022.Based on the issues and challenges identified here,some future research directions are suggested.
文摘This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface preparation, coating application, as well as coating inspection for four types of major production facilities.
文摘In order to solve the problems related with processing low-quality Liaohe highly sour crude, the Liaohe Petrochemical Company has explored the possibility in optimizing the processing of highly sour crude by adopting different process schemes depending upon the properties of the highly sour crude. The Liaohe naphthenic-base crude oil with low freezing point is earmarked for manufacture of naphthenic lube oils and heavy traffic paving asphalt, while the extra-heavy Liaohe crude with high acid number is routed directly to delayed coking unit coupled with corresponding corrosion preventing measures, resulting in tackling the problem of equipment corrosion arising from refining of Liaohe highly sour crude to obtain light distillates from Liaohe heavy crude through a short process scheme.
文摘The corrosion resistance of NiCrBSi coating deposited on steel substrate by HVOF was examined using electrochemical tests and immersion tests so as to offer an experimental basis to expand a promising applied field of HVOF in aqueous medium, comparing with those of coatings deposited by oxyacetylene flame spraying and flame cladding. The results show that the general corrosion rate of HVOF sprayed coatings is quite bigger than that of clad coatings, but it is less sensitive to local corrosion. There is less and smaller porosity in the coatings deposited by HVOF than that in flame sprayed coatings. The effects of porosity on the corrosion current density was indistinctive, but the existence of large amount of defects in the coatings damaged the cohesion of the coatings, causing the metallic particles drop off from the coatings under the influence of corrosive medium. Improving the quality and reducing the porosity of coatings is the key to get the coatings with high corrosion resistance.
基金financially supported by the National Natural Science Foundation of China(Nos.U19A2096,51903030,52021001)。
文摘Carbonyl iron(CI)particles as magnetic microwave absorption material often suffer from serious corrosion under corrosive environment which leads to performance deterioration.In this study,fluorin-containing acrylate type polymer network layers with thickness ranging from tens of nanometers to around one hundred nanometers were formed continuously around CI.The crosslinked coating layer(named FT)effectively increases CI’s thermal decomposition temperature by at least 34%.The FT-coated CI(named CI-FT)was able to resist both inorganic and organic corrosive media attacking efficiently compared with bare CI.The surface polymer network could also help CI withstand organic medium dissolution which proved the firmness of coating.Cyclic voltammetry(CV)test revealed that the coating layer could significantly reduce maximum oxidation current density of CI by more than 45 times.Tafel polarization study during CV tests also confirmed that thicker FT coating layer could help CI sample stabilize corrosion current density.Meanwhile,the surface coating also enhanced the impedance matching properties of CI as microwave absorber and the CI-FT samples demonstrated improved microwave absorption properties which degenerated little after corrosive medium soaking compared with that of CI.
