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Evolution of the corrosion product film and Its Effect on the Erosion–corrosion Behavior of Two Commercial 90Cu–10Ni Tubes in Seawater

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Acta Metallurgica Sinica(English Letters) 2018年第11期31卷 1148-1170页

作者： Okpo O. Ekerenam Ai-Li Ma Yu-Gui Zheng Si-Yu He Peter C. Okafor CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academyof Sciences Shenyang 110016 China University of Chinese Academy of Sciences (UCAS) Beijing 100049 China Department of Pure and Applied Chemistry University of Calabar PMB 1115 Calabar CRS Nigeria

The composition and structural evolution of the corrosion product film of two commercial 90Cu-10Ni tubes, namely TubeA and Tube B, after being immersed in natural seawater for 1, 3, and 6 months were characterized by scanning electronmicroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy, and its effecton the erosion--corrosion behavior of the tubes was determined through a rotating cylinder electrode system using variouselectrochemical techniques. For the freshly polished samples used as contrast samples, the flow velocity mainly enhancedthe cathodic reaction at low flow velocities while both the anodic and the cathodic reactions were remarkably accelerated athigher flow velocities. The corrosion product films formed on the two commercial 90Cu-10Ni tubes after being immersedin seawater for up to 6 months are of a complex three-layer or multilayer structure. The structural evolution of the films isout of sync for the two tubes. A continuous residual substrate layer depleted of Ni was observed in the inner layer of thefilms on Tube B after 30, 90, and 180 days＇ immersion, while it was observed in the film on Tube A only after 180 days＇immersion. The nature of the inner layer plays a crucial role in the erosion-corrosion resistance of the 90Cu-10Ni tubes athigher flow velocity. The film with a compact and continuous inner layer of Cu20 doped with Ni2＋ and Ni3＋ which bondsfirmly with the substrate could survive and even get repaired with the increased flow velocity. The film on Tube Bpossessing a hollow and discontinuous inner layer composed of the residual substrate was degraded rapidly with increasingrotation speed in spite of its quite good resistance at the stagnant or lower speed conditions.

关键词： Copper-nickel alloy Seawater immersion Erosion-corrosion corrosion product film Flow velocity

Effect of Zn on mechanical and corrosion properties of Mg-Sc-Zn alloys

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Journal of Materials Science & Technology 2023年第27期158卷 31-42页

作者： Wenjun Ci Xianhua Chen Yue Sun Xu Dai Guanzheng Zhu Di Zhao Fusheng Pan International Joint Laboratory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400045China State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044China School of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China

The effect of different Zn concentrations(0 wt.%,1 wt.%,3 wt.%,and 6 wt.%)on the microstructure,cor-rosion property,and mechanical property of Mg-0.3Sc-x Zn(x=0 wt.%,1 wt.%,3 wt.%,and 6 wt.%)alloys was investigated.Here,MSZ1 alloy exhibits the highest corrosion resistance(0.194 mm/y)and appropriate mechanical properties with an ultimate tensile strength of 228 MPa and elongation of 19%.The superior corrosion resistance of Mg-0.3Sc-1Zn alloys is attributed to the homogeneous volta-potential distribution and the dense corrosion product film.With the increase in zinc content,the strength and plasticity of Mg-0.3Sc-x Zn alloys(x=0 wt.%,1 wt.%,3 wt.%,6 wt.%)improved to some extent.The precipitated ScZn phase plays the role of the second phase strengthening,which enables MSZ6 to obtain the maximum tensile strength.However,the ScZn phase with low volta potential intensifies the galvanic corrosion,re-sulting in the decline of the corrosion performance.

关键词： High corrosion resistance Mechanical performance Mg-Sc-Zn alloys SKPFM corrosion product film

Research on the corrosion of J55 Steel Due to Oxygen-Reducing Air Flooding in Low-Permeability Reservoirs

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Fluid Dynamics & Materials Processing 2023年第7期19卷 1925-1937页

作者： Liang Wang Baofeng Hou Yanming Fang Jintao Zhang Fajian Nie School of Petroleum Engineering Yangtze UniversityWuhan430100China Beijing Huacheng Hengye Petroleum Technology Development Limited Company Beijing101499China Petroleum Engineering Technology Research Institute of North China Oil&Gas Company Zhengzhou450006China

Oxygen-reducing air flooding is a low-permeability reservoir recovery technology with safety and low-cost advantages.However,in the process of air injection and drive,carbon in the air is oxidized through the crude oil reservoir to generate CO_(2),and this can cause serious corrosion in the recovery well.In this study,experiments on the corrosion of J55 tubular steel in a fluid environment with coexisting O_(2)and CO_(2)in an autoclave are presented.In particular,a weight loss method and a 3D morphometer were used to determine the average and the local corrosion rate.The corrosion surface morphology and composition were also measured by means of scanning electron microscopy(SEM)and an X-ray diffractometer(XRD).The corrosion pattern and morphological characteristics of J55 steel were analyzed in the O2/CO_(2)environment for different degrees of oxygen-reduction.As made evident by the experimental results,the corrosion products were mainly ferrous carbonate and iron oxide.In general,air injection increases the degree of oxygen reduction,from oxygen corrosion characteristics to CO_(2)corrosion-based characteristics.As a result,the corrosion product film becomes denser,and the corrosion rate is lower.

关键词： J55 steel O_(2)/CO_(2)corrosion corrosion product film oxygen-reducing air flooding

Protective Characteristics and Formation Mechanism of the corrosion product films of B30 Tubes Exposed to Seawater

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Journal of Materials Science & Technology 1992年第3期8卷 192-196页

作者：朱小龙林乐耘 Surface Technology Center General Research Institute for Nonferrous MetalsBeijing110083China To whom correspondence should be addressed Surface Technology Center General Research Institute for Nonferrous MetalsBeijing110083China

The corrosion product films of two kinds of B30 tubes(similar to CDA 715)exposed to seawat- er for various periods of time were investigated by SEM,AES and XPS.The results show that the pro- tective corrosion product film is thin,uniform and adherent.FeOOH is found to be present in the film surface,which confirms the hypothesis that iron hydroxide segregates at the surface of the film.The FeOOH promotes Ni enrichment in the corrosion layer by preventing Ni from running off.The corro- sion product film with no protectiveness is of lay- ered structure,loose and bad adherence.The for- mer film is formed through direct oxidation and the latter by precipitation and redeposition from dis- solved species.

关键词： Cu-Ni alloy corrosion product film exposure

corrosion Performance of Carbon Steel in CO_(2) Aqueous Environment Containing Silty Sand with Different Sizes

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Acta Metallurgica Sinica(English Letters) 2017年第11期30卷 1055-1066页

作者： Songle Lu Wei Liu Shian Zhang Xiaolong Qi Xiaogang Li Xuemin Wang corrosion and Protection Center Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Scienceand Technology Beijing Beijing 100083 China

corrosion performance of carbon steel in CO2 aqueous environment containing silty sand with different sizes was investigated by immersion tests and electrochemical measurements. Silty sand could form an adsorption layer on steel surface in initial period, and the sand adsorption layer was turned into a mixture film of silty sand with corrosion product in last period. The adsorption layer in 325 mesh condition （large size） had the fewest pores for H2CO3 transport, exhibiting the highest cathodic current inhibition. In spite of little corrosion product, the sand adsorption film formed in 325 mesh condition induced the lowest corrosion rate. For 1000 and 5000 mesh silty sand, the sand adsorption layer had some pores for H2CO3 transport, leading to low cathodic current inhibition and much matrix dissolution. But the adsorption layer for 5000 mesh silty sand （small size） had the largest special surface area to accelerate heterogeneous precipitation of corrosion product FeCO3. Therefore, the mixture film in 5000 mesh condition was more compact, exhibiting stronger anodic inhibition and lower corrosion rate than those in 1000 mesh condition.

关键词： Silty sand Sand adsorption layer corrosion product film corrosion inhibition Carbon steel

Multi-physics analysis of the galvanic corrosion of Mg-steel couple under the influence of time-dependent anisotropic deposition film

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Journal of Magnesium and Alloys 2021年第3期9卷 866-882页

作者： Kai Wang Chenpei Li Yanhui Li Jinling Lu Yueshe Wang Xingqi Luo State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi'an University of TechnologyNo.5 Jinhua South RoadXi'an 710048China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityNo.28 Xianning West RoadXi'an 710049China

The anisotropic deposit film formed during the galvanic corrosion can impede the mass transfer of the involved species,thereby affecting the electro-chemical behavior and the evolution of galvanic corrosion.The limitations of experimental studies in the spatial-temporal scales restrict a deeper understanding of the corrosion mechanism,which can be complemented by numerical simulation.A multi-physics coupled model is proposed in this work to systematically investigate the temporal and spatial evolution of galvanic corrosion of the Mg-steel couple with the growing anisotropic deposition layer.By utilizing the multi-physics field coupled technique,various coupled physical-chemical processes underlying the corrosion behavior are built into the model,including chemical reactions,ionic mass transfer in the bulk solution and the deposition layer,interfacial reaction,deposition of corrosion products as well as the morphological transitions caused by metal dissolution and deposition.In particular,the anisotropic deposit film is considered to be a porous layer with a porosity varying in time and space as the corrosion evolves.The predicted corrosion morphology by this model is better than the previous models.The coupled relationship between the electrochemical behavior(e.g.,electrode reaction kinetics,current density,surface potential)and the physical processes(e.g.,ionic transport,geometric evolution of metal surface and film interface)is revealed.The results indicate that a porous deposition layer with a denser inner layer and a loose outer layer is generated,leading to more significant inhibition of mass transfer in the inner layer than the outer layer.The anisotropism of the deposition layer results in a non-uniform conductivity distribution and a discontinuous current density distribution in the electrolyte.The current density on the electrode surface is inhibited by the deposition layer and the variation in the cathode/anode area ratio during the corrosion process.The competition between the transport process and the

关键词： Galvanic corrosion corrosion product film Modeling Mass transport Porosity

INFLUENCE OF THE MICROSTRUCTURE OF Cu-Ni ALLOY ON ITS corrosion RESISTANCE

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Transactions of Nonferrous Metals Society of China 1992年第4期2卷 51-55页

作者： Zhu Xiaolong General Research Institute for Nonferrous Metals Beijing 100088China

The microstructures of two kinds of Cu-Ni alloys were observed by TEM.The results show that one of the alloys is a homogeneous solid solution.The other contains discontinuous precipitates at some grain boundaries,and the precipitate is a phase rich in Fe-Ni.By monitoring the corrosion potential(E_(con))in artifical seawater and exposure to natural seawater for a long time,it is found that the E_(con)of the former alloy steadily decreases,while the E_(con)of the latter decreases a little and fluctuates,and the corrosion rate of the former is clearly lower than that of the latter.Aanalyses of SEM and EDX show that the corrosion product film of the former is thin,uniform,compact and rich in nickel,and the film of the latter is thick,loose and covered with numerous deposits.Additionally serious intergranular corrosion occurs in the underlying substrate of the latter.The author proposes that the intergraular corrosion results from preferential dissolution of discontinuous precipitates at grain boundaries.In addition,the protective characteristics of corrosion product films are related not only to the enrichment of nickel but also to their compactness.

关键词： Cu-Ni alloy microstructure corrosion resistance seawater corrosion potential corrosion product film