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Journal of Magnesium and Alloys 2020年第3期8卷 692-715页

作者： Ashutosh Jangde S.Kumar c.blawert Department of Materials Engineering Indian Institute of ScienceBangalore 560012India Institute of Materials Research Helmholtz-Zentrum GeesthachtMax-Planck-Str.121502 GeesthachtGermany

PEO coatings were synthesized from phosphate-based (bP-PEO) and glycerol added phosphate-based (gP-PEO) electrolytes with differentprocessing times. For both bP-PEO and gP-PEO coatings treated with different processing time its morphology, elemental and phase composition,and electrochemical behaviour has been comparatively investigated. For this, scanning electron microscope (SEM), energy-dispersiveX-ray spectroscopy (EDXS), X-ray diffraction, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization techniqueswere employed. The gP-PEO coatings were observed to have higher pore density with reduced pores size, surface porosity, and averagecoating thickness compared to bP-PEO for all the PEO processing time. XRD studies revealed that glycerol addition resulted in the fosteringof crystalline MgO (periclase) phase and promoting Mg3(PO4)2 (farringtonite) phase amorphization. In general, electrochemical behaviourshowed improved corrosion behaviour for gP-PEO compared to bP-PEO.

关键词： Magnesium alloy Plasma electrolytic oxidation Glycerol additive Electrochemical impedance spectroscopy corrosion.

In situ formation of LDH-based nanocontainers on the surface of AZ91 magnesium alloy and detailed investigation of their crystal structure

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Journal of Magnesium and Alloys 2022年第5期10卷 1268-1285页

作者： Tatsiana Shulha M.Serdechnova M.H.Iuzviuk I.A.Zobkalo P.Karlova N.Scharnagl D.c.F.Wieland S.V.Lamaka A.A.Yaremchenko c.blawert M.L.Zheludkevich Helmholtz-Zentrum Hereon Institute of Surface ScienceMax-Planck-Straβe 1Geesthacht 21502Germany condensed Matter Department Petersburg Nuclear Physics Institute Named by B.P.Konstantinov of National Research Center“Kurchatov Institute”MKR Orlova roshcha 1Gatchina 188300Russian Federation Helmholtz-Zentrum Hereon Institute of Metallic BiomaterialsMax-Planck Straβe 1Geesthacht 21502Germany Department of Materials and ceramic Engineering CICECO–Aveiro Institute of MaterialsUniversity of AveiroAveiro 3810-193Portugal Faculty of Engineering University of KielKaiserstraβe 2Kiel 24143Germany

In the presented work, the possibility of direct synthesis of LDH(layered double hydroxide) on the AZ91 surface in the presence of a chelating agent(diethylenetriaminepentaacetic acid-DTPA) is reported. conversion layer of LDH nanocontainers were formed under ambient pressure conditions without carbonate addition in the electrolyte. The obtained LDH was characterized using experimental(SEM,XRD, TGA, XPS, Raman, etc.) and computational methods(thermodynamic calculation, modeling of possible LDH crystal structures). A comparison of three possible LDHs(LDH-OH,-NO_(3) and-cO_(3)) was performed. Based on the experimental results and crystal simulation approach, it was confirmed, that the mixed LDH-OH/cO_(3) is grown on the surface in the presence of DTPA pentasodium salt.

关键词： Layered double hydroxides Magnesium alloy chelating agent Functional coating

Review of studies on corrosion of magnesium alloys

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中国有色金属学会会刊：英文版 2006年第B2期16卷 763-771页

作者：曾荣昌张津黄伟九 W.DIETZEL K.U.KAINER c.blawert 柯伟 School of Material Science and Engineering chongqing Institute of Technology Chongqing 400050China School of Material Science and Engineering chongqing Institute of Technology Chongqing 400050 China GKSS-Forschungszentrum Geesthacht GmbH Geesthacht 21502 Germany Environment corrosion centerInstitute of Metals Research Shenyang 110016China

This review provided some recent progress of the research on corrosion mechanisms of magnesium and its alloys and a basis for follow-on research. Galvanic corrosion, pitting corrosion, intergranular corrosion (IGc), filiform corrosion, crevice corrosion, stress corrosion cracking (Scc), and corrosion fatigue (cF) were discussed. The influence of metallurgical factors such as alloying elements, microstructure and secondary phases, processing factors such as heat treatment and weld, and environmental factors including temperature, relative humidity, solution pH values and concentration on corrosion were discussed. In particular, a mechanism of pitting corrosion caused by AlMn particles was proposed. The corrosion properties of AZ91D weld material were investigated.

关键词：镁合金腐蚀疲劳相对湿度研究综述

Plasma electrolytic oxidation of AZ31 and AZ91 magnesium alloys:comparison of coatings formation mechanism

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Journal of Magnesium and Alloys 2020年第3期8卷 587-600页

作者： A.G.Rakoch E.P.Monakhova Z.V.Khabibullina M.Serdechnova c.blawert M.L.Zheludkevich A.A.Gladkova aDepartment of Metal Protection and Surface Treatment National University of Science and Technology‘MISiS’Leninskiy prospekt 4119049 MoscowRussia Helmholtz-Zentrum Geesthacht Centre for Materials and Coastal Research GmbHMax-Plank Str.l21502 GeesthachtGermany Faculty of Engineering Kiel UniversityKaiserstrasse 224143 KielGermany

The growth kinetics of PEO coatings on AZ31 and AZ91 magnesium alloys were studied and correlated with their structure,compositions(phase and elemental)and corrosion *** was established that the coatings have a two-(outer and anodic)or three-layer structure(outer,inner and anodic)depending on the treatment ***,at short treatment time only an anodic layer and outer layer *** of the outer PEO layer takes place due to the micro discharges,which occur in vertical pores and voids with spherical *** the time is increasing,and electrolyte inside of the pores is heating-up,etching of the Mg substrate and oxide film becomes more dominant and horizontal pores in the interface between coating and metal are *** the pores new anodic layer will form and at this time the formation of the third inner layer *** growth of the inner layer happens via the anodic film as a result of micro discharge ignition in the horizontal pores,accompanied by formation of plasma in numerous micro-voids of this *** coatings formed on AZ91 alloy are denser,than those on AZ31,which is related to the difference in the rates of inner layer growth and dissolving of oxides which are located at the bottom of the horizontal *** of the lower Al content,the AZ31 substrate itself and the also the oxide films are less stable and tend to dissolve at a higher rate compared to ***,it was demonstrated that a good corrosion resistance of the coatings was only obtained on AZ91 and if the average thickness of the coating is around 50μm,correlating with the formation of a sufficiently dense inner laye-Knowing this mechanism,a new two-step treatment was suggested,combining the standard PEO treatment with a subsequent PEO process in an electrolyte supporting the inner film *** concept was successfully applied and a further improved corrosion resistance was obtained compared to the single stage PEO *** improvement of corrosion re

关键词： Plasma electrolytic oxidation Magnesium alloys coating formation coating growth corrosion resistance.

corrosion behavior of Mg-Gd-Zn based alloys in aqueous Nacl solution

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Journal of Magnesium and Alloys 2014年第3期2卷 245-256页

作者： A.Srinivasan c.blawert Y.Huang c.L.Mendis K.U.Kainer N.Hort Helmholtz-Zentrum GeesthachtInstitute of Materials ResearchMax-Planck-Str.121502 GeesthachtGermany cSIR-National Institute for Interdisciplinary Science and Technology Pappanamcode(P.O)Thiruvananthapuram 695019India

The corrosion behavior of Mg-10Gd-xZn(x=2,6 wt.%)alloys in 0.5 wt.%Nacl solution was *** of both the alloys consisted of(Mg,Zn)_(3) Gd phase and lamellar long period stacking ordered(LPSO)*** morphology of the second phase at the grain boundary differed in both alloys:it was a continuous network structure in Mg-10Gd-6Zn,whereas it was relatively discrete in *** dendrites were finer in size and highly branched in *** corrosion results indicated that the increase in Zn content increased the corrosion rate in Mg-10Gd-xZn ***-galvanic corrosion occurred near the grain boundary in both alloys initially as the grain boundary phase was stable and acted as a cathode,however,filiform corrosion dominated in the later stage,which was facilitated by the LPSO phase in the *** micro-galvanic corrosion occurred in Mg-10Gd-6Zn due to the higher volume of second *** stability of the second phase at the grain boundary was altered and dissolved after the long immersion *** the Nacl solution chemically reacted with the grain boundary phase and de-stabilized it during the long immersion times,and was removed by the chromic acid used for the corrosion product removal.

关键词： Mg-Gd-Zn alloys Micro-galvanic corrosion Polarization Electrochemical characterization

AZ31镁合金激光焊件的力学性能和应力腐蚀行为(英文)

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Transactions of Nonferrous Metals Society of china 2011年第1期21卷 1-8页

作者： P.B.SRINIVASAN S.RIEKEHR c.blawert W.DIETZEL M.KO AK Institute of Materials Research GKSS-Forschungszentrum Geesthacht GmbH Geesthacht D-21502Germany

采用Nd-YAG激光对AZ31 HP镁合金进行激光自熔焊接。显微组织分析表明,使用或不使用填料(焊料)AZ61镁合金得到的激光焊接接头的平均晶粒尺寸大约为12μm,显微硬度和拉伸强度与母材相近。然而,慢应变速率拉伸表明,在ASTM D1384溶液中两种... 详细信息

采用Nd-YAG激光对AZ31 HP镁合金进行激光自熔焊接。显微组织分析表明,使用或不使用填料(焊料)AZ61镁合金得到的激光焊接接头的平均晶粒尺寸大约为12μm,显微硬度和拉伸强度与母材相近。然而,慢应变速率拉伸表明,在ASTM D1384溶液中两种焊接接头的抗应力腐蚀性能比母材略差。可观察到应力腐蚀裂纹在焊缝金属萌生并向热影响区(HAZ)扩展。然而,在以AZ61镁合金为填料(焊料)获得的焊接接头中,观察到裂纹起源及扩展出现在热影响区(HAZ)。在慢应变速率拉伸试验中,由于试样表面暴露在腐蚀环境中,在氢氧化镁/氧化镁层形成局部损伤,从而导致应力腐蚀裂纹的生成。

关键词：镁合金激光焊接显微组织力学性能慢应变速率拉伸应力腐蚀裂纹断面分析

Effect of low concentration electrolytes on the formation and corrosion resistance of PEO coatings on AM50 magnesium alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1386-1405页

作者： Peng Xie carsten blawert Maria Serdechnova Natalia Konchakova Tatsiana Shulha Ting Wu Mikhail L.Zheludkevich Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Strasse 121502 GeesthachtGermany Institute for Materials Science Faculty of EngineeringKiel UniversityKaiserstrasse 224143 KielGermany

In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically *** results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other *** coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte *** coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test *** application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate ***,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.

关键词： Plasma electrolytic oxidation Low concentration electrolytes corrosion resistance AM50 magnesium alloy

镁表面Nafion聚/吡咯与Nafion二/甲基亚砜有机涂层耐蚀性能的研究

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材料保护 2007年第1期40卷 1-2,72页

作者：宋仁国郑晓华杨芳儿 c.blawert W.Dietzel 浙江工业大学机械制造及自动化教育部重点实验室浙江杭州310014 center for Magnesium Technology Institute of Materials Research GKSS-Forschungszentrum Geesthacht GmbH

采用浸镀法在镁基体表面制备了Nafion聚/吡咯和Nafion二/甲基亚砜(DMSO)有机涂层,利用光学显微镜和电化学测量系统研究了有机涂层的形貌及其耐蚀性能。结果表明,Nafion聚/吡咯有机涂层的厚度随着浸镀次数的增加几乎不变,且Nafion聚/吡... 详细信息

采用浸镀法在镁基体表面制备了Nafion聚/吡咯和Nafion二/甲基亚砜(DMSO)有机涂层,利用光学显微镜和电化学测量系统研究了有机涂层的形貌及其耐蚀性能。结果表明,Nafion聚/吡咯有机涂层的厚度随着浸镀次数的增加几乎不变,且Nafion聚/吡咯有机涂层降低了镁的耐蚀性能;而Nafion/DMSO有机涂层的厚度则随着浸镀次数的增加而线性增加,并且Nafion/DMSO有机涂层能有效地改善镁的耐蚀性能,耐蚀性能随着涂层厚度的增加而提高。与无涂层的试样相比,耐蚀性能最高提高18倍。

关键词：镁 Nation/聚吡咯有机涂层 Nation/二基亚砜有机涂层耐蚀性能

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铁配合型镁合金缓蚀剂的阴极阻蚀机制

Transactions of Nonferrous Metals Society of china 2024年第5期34卷 1496-1506页

作者：杨俊杰王霖倩 carsten blawert Sviatlana VLAMAKA christian FEILER Mikhail LZHELUDKEVIcH 李卫暨南大学先进耐磨蚀及功能材料研究院广州510632 暨南大学韶关研究院韶关512027 Institute of Surface Science Helmholtz-Zentrum Hereon(Hereon)21502 GeesthachtGermany Faculty of Engineering University of KielKaiserstraße 224143 KielGermany

研究阴极缓蚀剂(3-甲基水杨酸盐,3-MeSA)对含铁纯镁腐蚀性能的影响。高铁杂质颗粒成分、腐蚀表面形貌以及3-MeSA分子结构特征为揭示含铁镁合金的腐蚀行为及3-MeSA的阴极型阻蚀机理提供了实验与理论依据。研究结果表明:含铁杂质颗粒中含... 详细信息

研究阴极缓蚀剂(3-甲基水杨酸盐,3-MeSA)对含铁纯镁腐蚀性能的影响。高铁杂质颗粒成分、腐蚀表面形貌以及3-MeSA分子结构特征为揭示含铁镁合金的腐蚀行为及3-MeSA的阴极型阻蚀机理提供了实验与理论依据。研究结果表明:含铁杂质颗粒中含有固溶态硅,而Fe/Si比可能是导致不同局部腐蚀形态差异的主要原因。虽然3-MeSA能在镁基体上形成吸附层,但其阻蚀机制主要归因于其螯合从富铁颗粒中自腐蚀释放Fe^(2+)/Fe^(3+)的能力,阻止被还原的铁物质再次沉积至腐蚀金属表面。

关键词：镁富铁杂质铁配合剂阴极型缓蚀剂量子化学计算

A toast to a zebrafish germ cell induction cocktail

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Science china(Life Sciences) 2024年第6期67卷 1314-1315页

作者： Mary c.Mullins Department of cell and Developmental Biology University of Pennsylvania Perelman School of MedicinePhiladelphia 19104USA

The zebrafish field is ringing in the new year with a publication from Yonghua Sun's laboratory(Wang et al.,2023)of a cocktail of germline factors that can induce all cells of the zebrafish embryo into primordial germ cells(PGcs)at phenomenal *** major advance is not only of great interest to germ cell biologists,but it has important applications to the entire zebrafish field,as shown in Wang et al.(2023).

关键词： fish zebra field

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