The Experts below are selected from a list of 28830 Experts worldwide ranked by ideXlab platform
Xiaogang Li - One of the best experts on this subject based on the ideXlab platform.
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atmospheric corrosion behavior and mechanism of a ni advanced weathering steel in simulated tropical Marine environment
Journal of Materials Engineering and Performance, 2017Co-Authors: Wei Wu, Xuequn Cheng, Zhongping Zeng, Xiaogang LiAbstract:Corrosion behavior of Ni-advanced weathering steel, as well as carbon steel and conventional weathering steel, in a simulated tropical Marine Atmosphere was studied by field exposure and indoor simulation tests. Meanwhile, morphology and composition of corrosion products formed on the exposed steels were surveyed through scanning electron microscopy, energy-dispersive x-ray spectroscopy and x-ray diffraction. Results indicated that the additive Ni in weathering steel played an important role during the corrosion process, which took part in the formation of corrosion products, enriched in the inner rust layer and promoted the transformation from loose γ-FeOOH to dense α-FeOOH. As a result, the main aggressive ion, i.e., Cl−, was effectively separated in the outer rust layer which leads to the lowest corrosion rate among these tested steels. Thus, the resistance of Ni-advanced weathering steel to atmospheric corrosion was significantly improved in a simulated tropical Marine environment.
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the corrosion behavior of pcb imag in industry polluted Marine Atmosphere environment
Materials & Design, 2017Co-Authors: Kui Xiao, Xiaogang Li, Pan Yi, Chaofang Dong, Junsheng Wu, Li JiangAbstract:This experiment was carried out in Wheat Island Qingdao which is characterized with a typical industrial polluted Marine Atmosphere environment. The Atmosphere contains a large amount of Cl− and SO2. The corrosion mechanism of printed circuit boards (PCBs) with an immersion silver surface finish (PCB-ImAg) in this phenomenon is still unknown. The corrosion behavior of PCB-ImAg is different under the influences of Cl− and SO2. Silver has strong resistance to Cl−, which mainly causes micro-hole corrosion. However, silver is sensitive to SO2. The corrosion degree can be accelerated in the environment containing Cl− and SO2. In this environment, the main corrosion products are oxides, sulfate and carbonate of silver and copper. The results summarized in this paper indicated that PCB-ImAg cannot be used in industrially polluted Marine environment. Protective measures such as conformal coating are necessary to protect PCB-ImAg.
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atmospheric corrosion of field exposed az31 magnesium in a tropical Marine environment
Corrosion Science, 2013Co-Authors: Xiaogang Li, Kui Xiao, Chaofang DongAbstract:Corrosion behavior of AZ31 magnesium in tropical Marine Atmosphere was investigated. Chloride ions deposition rate played an important role in the corrosion process, which resulted in an obvious fluctuation of the corrosion rate. The corrosion was initiated from pitting corrosion and then evolved into general corrosion as the exposure time extended. Mg5(CO3)4(OH)2·xH2O was the dominate products during the whole exposure periods. The products on the specimens weathered for 1, 6 and 12 months slightly suppressed the corrosion process, while that generated after 24 months of exposure exhibited good protective ability against further corrosion attacks.
Zhongyu Cui - One of the best experts on this subject based on the ideXlab platform.
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influence of different heat affected zone microstructures on the stress corrosion behavior and mechanism of high strength low alloy steel in a sulfurated Marine Atmosphere
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2019Co-Authors: Zhiyong Liu, Zhongyu CuiAbstract:Abstract The stress corrosion cracking (SCC) behavior and mechanism of the simulated heat-affected zone (HAZ) of high-strength low-alloy (HSLA) steel in a sulfurated Marine Atmosphere were surveyed in detail using electrochemical measurements and slow strain rate tensile (SSRT) tests combined with microstructure analysis. The SCC of the simulated HAZs is controlled by both anodic dissolution (AD) and hydrogen embrittlement (HE), which are attributed to the synergistic effect of Cl− and SO42−, as Cl−-induced localized dissolution causes microcrack initiation, and SO42--catalyzed acid regeneration facilitates microcrack propagation. The intercritical HAZ and fine-grained HAZ present high crack numbers because of the high amount of prior austenite grain boundaries (PAGBs), lath bainite boundaries (LBBs), and martensite/austenite (M/A) constituents, which act as preferential sites for hydrogen trapping and crack initiation. However, coarse-grained HAZ exhibits the highest SCC susceptibility because of the coarse PAGBs, wide lath bainites (LBs), and high local dislocation density, which promote crack propagation.
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comparative study of the scc behavior of e690 steel and simulated haz microstructures in a so2 polluted Marine Atmosphere
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2016Co-Authors: Zhiyong Liu, Zhongyu CuiAbstract:Abstract Simulated microstructures of the typical CGHAZ, FGHAZ, and ICHAZ of an E690 welded joint were prepared with heat treatment at peak temperatures of 1300, 850, and 750 °C, respectively. Slow strain rate tensile (SSRT) tests were implemented to investigate the stress corrosion cracking (SCC) behavior of E690 steel and the simulated HAZ microstructures in a SO 2 -polluted Marine Atmosphere. Results revealed that E690 steel and its simulated HAZ microstructures all had a high SCC susceptibility in the simulated SO 2 -polluted Marine Atmosphere with a combined mechanism of AD and HE. The SCC susceptibility gradually increased in the following order: BM, CGHAZ, FGHAZ, and ICHAZ. The cracking mode of BM and CGHAZ was transgranular, whereas that of FGHAZ and ICHAZ was intergranular. The lower SCC susceptibility of BM and CGHAZ was probably due to the impeding effect of lath bainitic grain boundaries on SCC propagation, whereas the higher SCC susceptibility of FGHAZ and ICHAZ was attributed to the facilitating effect of M-A islands on crack initiation and propagation.
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exfoliation corrosion behavior of 2b06 aluminum alloy in a tropical Marine Atmosphere
Journal of Materials Engineering and Performance, 2015Co-Authors: Zhongyu Cui, Di Zhang, Kui Xiao, C F Dong, Lei Wang, Zhengjian LiuAbstract:In this study, corrosion behavior of 2B06 aluminum alloy was investigated after exposure to a tropical Marine Atmosphere for up to 4 years. After 6 months, the specimen showed exfoliation corrosion as well as rapid increase in thickness loss and corrosion rate. Exfoliation corrosion was found to initiate from hydrogen-assisted intergranular cracks and propagate extensively due to the wedge effect of the corrosion products. During the exposure test, corrosion on the groundward surface was considerably more severe than that on the skyward surface, which could be attributed to the different exposure conditions on the two surfaces.
Zhiyong Liu - One of the best experts on this subject based on the ideXlab platform.
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influence of different heat affected zone microstructures on the stress corrosion behavior and mechanism of high strength low alloy steel in a sulfurated Marine Atmosphere
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2019Co-Authors: Zhiyong Liu, Zhongyu CuiAbstract:Abstract The stress corrosion cracking (SCC) behavior and mechanism of the simulated heat-affected zone (HAZ) of high-strength low-alloy (HSLA) steel in a sulfurated Marine Atmosphere were surveyed in detail using electrochemical measurements and slow strain rate tensile (SSRT) tests combined with microstructure analysis. The SCC of the simulated HAZs is controlled by both anodic dissolution (AD) and hydrogen embrittlement (HE), which are attributed to the synergistic effect of Cl− and SO42−, as Cl−-induced localized dissolution causes microcrack initiation, and SO42--catalyzed acid regeneration facilitates microcrack propagation. The intercritical HAZ and fine-grained HAZ present high crack numbers because of the high amount of prior austenite grain boundaries (PAGBs), lath bainite boundaries (LBBs), and martensite/austenite (M/A) constituents, which act as preferential sites for hydrogen trapping and crack initiation. However, coarse-grained HAZ exhibits the highest SCC susceptibility because of the coarse PAGBs, wide lath bainites (LBs), and high local dislocation density, which promote crack propagation.
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effect of ph and hydrogen on the stress corrosion cracking behavior of duplex stainless steel in Marine Atmosphere environment
Ocean Engineering, 2017Co-Authors: Zhiyong LiuAbstract:Abstract Electrochemical and stress corrosion cracking (SCC) behaviors of 2205 duplex stainless steel (DSS) of different microstructures in the Marine Atmosphere environment with various pH values and hydrogen charging current densities were investigated by employing electrochemical measurements and the slow strain rate tensile (SSRT) method. Results indicated that the resistance of 2205 DSS to pitting corrosion deteriorated as the pH decreased, and the susceptibility to SCC improved in spite of the decrease in pH or the increase in hydrogen charging current density. As compared to the microstructure of the as-received specimen, microstructures of the normalized and especially the quenched samples were more vulnerable to SCC.
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comparative study of the scc behavior of e690 steel and simulated haz microstructures in a so2 polluted Marine Atmosphere
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2016Co-Authors: Zhiyong Liu, Zhongyu CuiAbstract:Abstract Simulated microstructures of the typical CGHAZ, FGHAZ, and ICHAZ of an E690 welded joint were prepared with heat treatment at peak temperatures of 1300, 850, and 750 °C, respectively. Slow strain rate tensile (SSRT) tests were implemented to investigate the stress corrosion cracking (SCC) behavior of E690 steel and the simulated HAZ microstructures in a SO 2 -polluted Marine Atmosphere. Results revealed that E690 steel and its simulated HAZ microstructures all had a high SCC susceptibility in the simulated SO 2 -polluted Marine Atmosphere with a combined mechanism of AD and HE. The SCC susceptibility gradually increased in the following order: BM, CGHAZ, FGHAZ, and ICHAZ. The cracking mode of BM and CGHAZ was transgranular, whereas that of FGHAZ and ICHAZ was intergranular. The lower SCC susceptibility of BM and CGHAZ was probably due to the impeding effect of lath bainitic grain boundaries on SCC propagation, whereas the higher SCC susceptibility of FGHAZ and ICHAZ was attributed to the facilitating effect of M-A islands on crack initiation and propagation.
Kui Xiao - One of the best experts on this subject based on the ideXlab platform.
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the corrosion behavior of pcb imag in industry polluted Marine Atmosphere environment
Materials & Design, 2017Co-Authors: Kui Xiao, Xiaogang Li, Pan Yi, Chaofang Dong, Junsheng Wu, Li JiangAbstract:This experiment was carried out in Wheat Island Qingdao which is characterized with a typical industrial polluted Marine Atmosphere environment. The Atmosphere contains a large amount of Cl− and SO2. The corrosion mechanism of printed circuit boards (PCBs) with an immersion silver surface finish (PCB-ImAg) in this phenomenon is still unknown. The corrosion behavior of PCB-ImAg is different under the influences of Cl− and SO2. Silver has strong resistance to Cl−, which mainly causes micro-hole corrosion. However, silver is sensitive to SO2. The corrosion degree can be accelerated in the environment containing Cl− and SO2. In this environment, the main corrosion products are oxides, sulfate and carbonate of silver and copper. The results summarized in this paper indicated that PCB-ImAg cannot be used in industrially polluted Marine environment. Protective measures such as conformal coating are necessary to protect PCB-ImAg.
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surface analysis of silver plated circuit boards in a salt spray environment
Journal of Alloys and Compounds, 2016Co-Authors: Lidan Yan, Kui Xiao, Chaofang Dong, Chengliang MaoAbstract:Abstract By conducting salt-spray tests, we studied the corrosion behaviour and mechanism of printed circuit boards with an immersion Ag surface finish (PCB-ImAg) in polluted environments that contain SO2 and Cl−. The polluted environment was similar to the polluted Marine Atmosphere environment in Qingdao China. A comparison of micrographs of the test specimens revealed that the test specimens containing SO2 and Cl− suffered more serious damage. The entire corrosion process resulted in unevenly distributed partial corrosion products at the initial stage. However, this distribution gradually became uniform. The Raman spectroscopic analysis results for the test specimens containing SO2 and Cl− show that the corrosion products mainly comprised Cu4(OH)6SO4, Cu2Cl(OH)3, Cu2O, Ag2O, Ag2CO3, Ag2SO3 and Ag2SO4.
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exfoliation corrosion behavior of 2b06 aluminum alloy in a tropical Marine Atmosphere
Journal of Materials Engineering and Performance, 2015Co-Authors: Zhongyu Cui, Di Zhang, Kui Xiao, C F Dong, Lei Wang, Zhengjian LiuAbstract:In this study, corrosion behavior of 2B06 aluminum alloy was investigated after exposure to a tropical Marine Atmosphere for up to 4 years. After 6 months, the specimen showed exfoliation corrosion as well as rapid increase in thickness loss and corrosion rate. Exfoliation corrosion was found to initiate from hydrogen-assisted intergranular cracks and propagate extensively due to the wedge effect of the corrosion products. During the exposure test, corrosion on the groundward surface was considerably more severe than that on the skyward surface, which could be attributed to the different exposure conditions on the two surfaces.
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atmospheric corrosion of field exposed az31 magnesium in a tropical Marine environment
Corrosion Science, 2013Co-Authors: Xiaogang Li, Kui Xiao, Chaofang DongAbstract:Corrosion behavior of AZ31 magnesium in tropical Marine Atmosphere was investigated. Chloride ions deposition rate played an important role in the corrosion process, which resulted in an obvious fluctuation of the corrosion rate. The corrosion was initiated from pitting corrosion and then evolved into general corrosion as the exposure time extended. Mg5(CO3)4(OH)2·xH2O was the dominate products during the whole exposure periods. The products on the specimens weathered for 1, 6 and 12 months slightly suppressed the corrosion process, while that generated after 24 months of exposure exhibited good protective ability against further corrosion attacks.
Xuequn Cheng - One of the best experts on this subject based on the ideXlab platform.
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insight into the product film formed on ni advanced weathering steel in a tropical Marine Atmosphere
Applied Surface Science, 2018Co-Authors: Xuequn Cheng, Huaxing Hou, Bo LiuAbstract:Abstract The product film formed on Ni-advanced weathering steel in a tropical Marine environment was investigated in detail through outdoor exposure by using diverse surface analysis techniques combined with electrochemical impedance spectroscopy and scanning kelvin probe measurements. The results showed that the product film was mainly composed of nanophasic goethite in the inner layer and maghemite, akaganeite, and hematite in the outer layer. Moreover, the resistance to atmospheric corrosion gradually increased from the outermost product film to the innermost film. Ni was significantly enriched in the inner layer in the form of the spinel phase NiFe2O4, which transformed lepidocrocite to fine-grained goethite, withstood the invasion of chloridion, and improved the corrosion potential of the product film in a tropical Marine Atmosphere.
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atmospheric corrosion behavior and mechanism of a ni advanced weathering steel in simulated tropical Marine environment
Journal of Materials Engineering and Performance, 2017Co-Authors: Wei Wu, Xuequn Cheng, Zhongping Zeng, Xiaogang LiAbstract:Corrosion behavior of Ni-advanced weathering steel, as well as carbon steel and conventional weathering steel, in a simulated tropical Marine Atmosphere was studied by field exposure and indoor simulation tests. Meanwhile, morphology and composition of corrosion products formed on the exposed steels were surveyed through scanning electron microscopy, energy-dispersive x-ray spectroscopy and x-ray diffraction. Results indicated that the additive Ni in weathering steel played an important role during the corrosion process, which took part in the formation of corrosion products, enriched in the inner rust layer and promoted the transformation from loose γ-FeOOH to dense α-FeOOH. As a result, the main aggressive ion, i.e., Cl−, was effectively separated in the outer rust layer which leads to the lowest corrosion rate among these tested steels. Thus, the resistance of Ni-advanced weathering steel to atmospheric corrosion was significantly improved in a simulated tropical Marine environment.
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corrosion behavior of nickel containing weathering steel in simulated Marine atmospheric environment
Materials and Corrosion-werkstoffe Und Korrosion, 2014Co-Authors: Xuequn Cheng, Yuwan Tian, Cheng ZhouAbstract:The influence of Ni on the corrosion behavior of Ni-containing weathering steel (Q415NH) was investigated under alternate dry/wet conditions. The results suggested that the addition of Ni shifted the corrosion potential of the steel to the positive direction and lowered the corrosion current density. Furthermore, the addition of Ni was in favor of the formation of a compact and homogeneous inner rust layer (composed of most α-FeOOH and little β-FeOOH), leading to enhanced corrosion resistance of the steel in the simulated Marine Atmosphere.
