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In this study, grit blasting with different abrasive particle sizes was carried out on magnesium alloy sheets, then the carbon fiber reinforced polymer (CFRP)/magnesium alloys laminates were prepared using a hot-press process. The surface characteristics of magnesium alloy, and the interlaminar strength of CFRP/Mg laminates were examined, in order to investigate comprehensively the effect of surface roughness on interlaminar strength of laminates under peel and shear loading conditions. The results show that the rougher surface significantly improves the peel strength of laminates, while the shear strength of laminates increases only slightly with increasing surface roughness. Hence, the rougher surface exhibits a good overall interlaminar strength under peel and shear loading when compared to the smoother surfaces. [ABSTRACT FROM AUTHOR]

In this study, the magnesium alloy sheet was treated by laser ablation to develop a type of conversion film on magnesium alloy aimed for simultaneous improvement in interlaminar strength and galvanic corrosion resistance of CFRP/Mg laminates. The results show that laser ablation can effectively enhance the Mode I (peel) interlaminar strength of CFRP/Mg laminates due to the formation of chaotic structure on the magnesium surface, and the peel strength decreases with the increase of scan speed. In addition, the laser ablation layer can provide an excellent protection against the galvanic corrosion in CFRP/Mg laminates, since the isolation between carbon fibre and magnesium substrate can be obtained by laser ablation. [ABSTRACT FROM AUTHOR]

In this work, three different surface modification techniques, including grit blasting, micro-arc oxidation (MAO) and laser ablation, were respectively carried out on magnesium alloy sheets, and then the treated surfaces were evaluated for surface topography and surface roughness characteristics. Besides, the interlaminar strength and the interface failure characteristics of the CFRP/Mg laminates were examined, in order to comprehensively analyze the effects of the various pre-treatment techniques on interlaminar strength and fracture mechanisms of the CFRP/Mg laminates under Mode I (peel) and Mode II (shear) loading. The results show that the MAO treatment resulted in a slight increase of shear strength when compared with grit blasted surfaces, yet it yields worse peel strength outcome due to the weak MAO coating/Mg substrate interface. The laser ablation effectively enhances the overall interlaminar strength of the CFRP/Mg laminates under peel and shear loading. [ABSTRACT FROM AUTHOR]

[Display omitted] • Geodetector based max-contribution improves the accuracy of flat urban extracting. • Contribution value varies associated with local urban development strategies. • Population is outstandingly with high contribution value in mountainous urbanization. • Geodetector based contribution increases as the categorized classes increasing. • The Gini importance of radon forest decreases as the number of independent variables increases. Urbanization induced changes have attracted widespread attention. Key challenges arise from the inherent uncertainties in attribution models diagnosing the driving mechanisms and the interrelationships of the attributes given by the complexity of interactions within a city. Here, we investigate urbanization dynamics from nighttime light signals before analyzing their driving mechanisms from 2014 to 2020 on both provincial and regional scale and a flat versus mountainous urbanization comparison. Model uncertainties are discussed comparing the contribution results from Geodetector and the Gini importance from Random Forest analyses. The method is applied to Shaanxi Province, where flat urban land is located mainly in its center and mountainous urban land is situated in the North and South. The following results are noted: i) Employing the Geodetector based maximum contribution method for urban region extraction of night time light reveals a notable accuracy improvement in flat urban land compared with the closest area method. ii) Geographical factors attain high contribution for mountainous urban land of Shannan, while for flat urbanization land dynamics, economic factors and community factors prevail. iii) The most obvious driving mechanisms are economic factors which, associated with local urban development strategies, show highest contribution values in 2014 (2018) over the flat (mountainous) urban land of Guanzhong Plain (Northern Shaanxi Plateau or Shanbei region) linked with an early (late) development. iv) Population factors achieve high contribution values in the initially low populated urban land of the northern mountainous land initiating huge migration. v) The contributions resulting from Geodetector are in agreement with the Gini importance from Random Forest in agriculture, geographical and population factors (R2 > 0.5) but not in economy, community and climatic factors (R2 < 0.5). The dynamics of driving mechanisms for urbanization provides insights in connecting urban geographical expansion with multi-factors and thus to assist municipal governments and city stakeholders to design a city with geographical, climatic and social-economic changes and interactions in mind. [ABSTRACT FROM AUTHOR]

The fiber metal laminates (FML), consisting of carbon fiber reinforced polymer prepregs and magnesium alloys sheets, were introduced, and the Mode I (peel) and Mode II (shear) interlaminar fracture toughness of the FMLs were investigated. The results show that the Mode I interlaminar toughness (0.23 kJ/m2) of the FMLs is much lower than the Mode II interlaminar toughness (5.81 kJ/m2), due to the fact that the effects of mechanical interlock to hinder crack propagates is smaller under Mode I loading conditions than under Mode II. The FMLs mainly show adhesive failure and interfacial failure under Mode I loading conditions, while for Mode II loading, it exhibits a degree of epoxy cohesive failure except the adhesive failure and interfacial failure. [ABSTRACT FROM PUBLISHER]

The galvanic corrosion behaviour of carbon fibre reinforced polymer (CFRP, T300/648) in contact with different magnesium alloys (AZ31, LZ91 and LZ141) in a sodium chloride solution and the influence of micro-arc oxidation (MAO) film on the corrosion behaviour of CFRP/magnesium alloys coupling were investigated using the electrochemical method. The results showed that the galvanic activity of CFRP/magnesium alloys coupling increased with the increase of lithium concentrations. The duration of the inhibitory effect of MAO film on the corrosion of CFRP/Mg–Li coupling is longer than that of CFRP/Mg–Al coupling due to its double-layer structure. [ABSTRACT FROM AUTHOR]