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Journal of Materials Science & Technology 2020年第4期39卷 39-47页

作者： Shanshan Chen bin Zhang bingchun Zhang Hao Lin Hui Yang Feng Zheng Ming Chen Ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Department of Cardiology of Peking University First Hospital Beijing 100034China

Magnesium alloy coronary stent becomes a hot research topic due to its biodegradable character for avoiding late thrombosis and late ***,fracture of Mg alloy stent was a common issue after *** this study,18 drug-eluting biodegradable az31 b stents were implanted into porcine coronary arteries to assess its structural integrity,corrosion behavior and microstructure change in *** coronary artery tissue responses to az31 b stent implantation were detected by quantitative coronary angiography and optical coherence tomography at the set time *** addition,further analyses were focused on the stent structure integrity,corrosion behaviors and the microstructure change of Mg alloy stents after implantation.A large number of fractures on stent struts were observed by high-resolution transmission X-ray tomography ***,degradation products,twins and grain refinement that appeared in Mg alloy stent matrix after implantation were also observed during the *** from this study,it is shown that the loss of az31 b stent structural integrity may be the result of stress concentration,degradation and microstructure change.

关键词： az31b Coronary stent Structural integrity Degradation Microstructure

Grain refinement and orientation of az31b magnesium alloy in hot flow forming under different thickness reductions

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Journal of Materials Science & Technology 2018年第7期34卷 1091-1102页

作者： Yalian Zhang Fenghua Wang Jie Dong Li Jin Conghui Liu Wenjiang Ding National Engineering Research Center of Light Alloy Net Forming & State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai Light Alloy Net Forming National Engineering Research Center Co. Ltd

An analysis of the hot flow forming of Mg-3.0Al-l.0Zn-0.3Mn （az31b） alloy was conducted by experiments and numerical simulations. The effects of different thickness reductions on the microstructure and mechanical properties were investigated at a temperature of 693 K, a spindle speed of 800 rev/min and a feed ratio of 0.1 mm/rev. Thickness reductions have great influence on the uniformity of microstructure along the radial direction （RD） and the grain sizes become refined and uniform when the thickness reduction reaches 45%. The c-axes of most grains are approximately parallel to the RD, with a slight inclination towards the axial direction （AD）. The best mechanical properties with UTS of 280 MPa and YS of 175 MPa near the outer surface while 266 MPa and 153 MPa near the inner surface have been achieved due to grain refinement and texture. Moreover, the material flow behavior and stress/strain distributions for singlepass reductions were studied using the AbAQUS/Explicit software. The calculated results indicate that the materials mainly suffer from triaxial compressive stresses and undergo compressive plastic strain in RD and tensile strains in other directions. The higher stress and strain rate near the outer surface lead to more refined grains than that of other regions along the RD, whereas the orientation of the maximum principal compressive stress leads to a discrepancy of the grain orientations in RD.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： az31b Hot flow forming Grain refinement Texture

Study of galvanic corrosion and mechanical joint properties of az31b and carbon-fiber–reinforced polymer joined by friction self-piercing riveting

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Journal of Magnesium and Alloys 2022年第2期10卷 434-445页

作者： Yong Chae Lim Jiheon Jun Donovan N.Leonard Yuan Li Jian Chen Michael P.brady Zhili Feng Materials Science and Technology Division Oak Ridge National LaboratoryOne Bethel Valley RoadOak RidgeTN 37831USA

A new testing methodology was developed to quantitively study galvanic corrosion of az31b and thermoset carbon-fiber–reinforced polymer spot-joined by a friction self-piercing riveting ***-defined areas of az31b in the joint were exposed in 0.1 M NaCl solution over *** galvanic corrosion of az31b was observed as exposure time *** measured volume loss was converted into corrosion current that was at least 48 times greater than the corrosion current of az31b without galvanic *** percent of the mechanical joint integrity was retained for corroded F-SPR joints to 200 h and then decreased because of the massive volume loss of az31b。

关键词： Multi-material joining Carbon fiber–reinforced polymer az31b Friction self-piercing riveting Galvanic corrosion Mechanical joint strength

Processing map for hot working of as extruded az31b magnesium alloy

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中国有色金属学会会刊：英文版 2005年第4期15卷 813-817页

作者：黄光胜黄光杰汪凌云潘复生 College of Materials Science and Engineering Chongqing University

The deformation behavior of az31b magnesium alloy as extruded under hot compression conditions was characterized in the temperature range of 200400℃ and strain rate range of 0.0011s^-1. The processing maps were obtained at different strains. The results show that the map exhibits flow instabilities as two domains. The domain at beyond 300℃ and strain rate of 1s^-1 appears with a peak efficiency of power dissipation about 56% occurring. This domain is expected to happen in a hot process, such as hot rolling, hot extrusion and hot forging. There is high efficiency of power dissipation at temperature beyond 350℃ and strain rate 0.001s^-*** domains suggest the occurrence of superplastic deformation.

关键词： az31b 镁合金挤压工艺金属加工过程管理热挤压

Synthesis of organic-inorganic 3D-nanocontainers for smart corrosion protection of friction stir welded az31b magnesium alloy-titanium dissimilar joints

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Journal of Magnesium and Alloys 2024年第9期12卷 3589-3601页

作者： Sepideh Aliasghari Teruo Hashimoto Peter Kelly Allan Matthews Henry Royce Institute Department of MaterialsThe University of ManchesterManchesterM139PLUK Department of Materials The University of ManchesterManchesterM139PLUK Surface Engineering Group Department of EngineeringManchester Metropolitan UniversityManchesterM15GDUK

The joining of different light metals through friction stir welding(FSW)is gaining interest as a method to decrease weight and improve fuel ***,to ensure durability,these welded metals may require surface treatments to protect against corrosion or *** study presents a novel approach for the simultaneous delivery of two distinct corrosion inhibitors to Ti-Mg dissimilar PEO treated joints on *** research focuses on the synthesis,characterization,and application of cerium@polystyrene(Ce@PS)nanocontainers,which are loaded with 8-hydroxyquinoline(8-HQ)to enhance corrosion *** synthesis involves several key steps,including the formation of a cerium-based outer layer around polystyrene nanospheres,the selective removal of the polystyrene core to create a porous structure,and the subsequent loading of the 8-HQ *** and compositional analyses,conducted using scanning transmission electron microscopy(STEM)and energy-dispersive X-ray spectroscopy(EDS),confirmed the successful incorporation of 8-HQ within the ***,Fourier-transform infrared spectroscopy(FTIR)provided detailed information about the chemical composition of the organic materials throughout the synthesis *** decomposition analysis verified the successful fabrication and stability of the dual-shell *** tests on Ti-Mg joints treated with plasma electrolytic oxidation(PEO)coatings and loaded nanocontainers demonstrated sig-nificantly improved corrosion resistance compared to untreated *** research highlights the potential of dual-shell nanocontainers,containing both organic and inorganic inhibitors,to offer prolonged corrosion protection,particularly against galvanic corrosion in dissimilar *** findings suggest that these synthesized nanocontainers hold promise for various industrial applications,particularly in the context of friction stir welded(FSW)Ti-Mg dissimilar joints,providing valuable

关键词： az31b Magnesium Dissimilar joint Two-shell inhibitors Smart corrosion protection

Effect of extrusion ratio on mechanical properties of az31b alloy

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中国有色金属学会会刊：英文版 2005年第S3期15卷 23-27页

作者：王海波洪艳梁宇询 College of Applied Science Harbin University of Science and Technology Harbin 150040 China College of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China

by optical microscope and scanning electron microscopy(SEM), the mechanical properties were mea- sured, the effect of extrusion ratio on the mechanical properties of az31b alloy was studied. The result shows that, with the increase of extrusion ratio, the microstructure becomes more fine and homogeneous. At low extrusion ra- tio, the crystalline grain is refined with increasing the extrusion, the tensile strength of the alloy is improved. At high extrusion ratio, the strength doesn’t increase and has the tendency to reduce instead again. When the extrusion ratio is 19.7, the strength is 265MPa, and when the extrusion ratio is 400, the strength is 295.5MPa, which improves about 10%. The specific elongation and contraction of area fall down with the increase of extrusion ratio. by SEM, many cleavage steps, cleavage tongues, dimples and tear ridges were detected in the fractures, which shows obvious mixed-fracture mechanisms.

关键词： az31b Mg alloy extrusion ratio mechanical property

Improving the Wear Resistance of az31b Magnesium Alloy by Laser Cladding with Al-Si/Al_2O_3-TiO_2 Powders

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稀有金属材料与工程 2011年第S4期40卷 169-173页

作者： Cui Zeqin1,2,Wang Wenxian1,2,Wu Hongliang1,Xu bingshe1,2 1Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology),Ministry of Education,Taiyuan 030024,China 2College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China Taiyuan Univ Technol Coll Mat Sci & Engn Taiyuan 030024 Peoples R China Taiyuan Univ Technol Minist Educ Key Lab Interface Sci & Engn Adv Mat Taiyuan 030024 Peoples R China

To improve the wear resistance of magnesium alloy,the laser surface cladding of az31b magnesium alloy with Al-12 % Si and Al2O3-40 % TiO2 composite powders (in the wt.% ratio of 10:1,6:1,4:1) were investigated by using a 5kW continuous wave CO2 laser.A detailed microstructure and phase analysis of the surface modified layer were studied by optics microscopy(OM),scanning electron microscopy(SEM),energy dispersive spectroscopy (EDS),X-ray diffraction(XRD).The microstructure of the surface modified layers mainly consist of Al-Mg matrix,dendrite precipitates and Al2O3,TiO2 ceramic *** microhardness of the surface layer were measured and wear resistance property were evaluated in *** average microhardness of the surface layers were significantly improved to 250HV0.05 as compared with 50HV0.05 of the az31b *** results showed that the wear resistance of the laser surface modified samples was considerably improved as compared as the as-received specimen.

关键词： az31b magnesium alloy laser cladding Al-Si/Al2O3-TiO2 powders wear resistance

Study on Characteristics and Generation Mechanism of YAG Pulsed Laser Welding Cracks of az31b Magnesium Alloy

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稀有金属材料与工程 2011年第S4期40卷 21-25页

作者： Cui Zeqin1,2,Wang Wenxian1,2,Si En1,Xu bingshe1,21Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology),Ministry of Education,Tai-yuan 030024,China2College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China Taiyuan Univ Technol Coll Mat Sci & Engn Taiyuan 030024 Peoples R China Taiyuan Univ Technol Key Lab Interface Sci & Engn Adv Mat Minist Educ Taiyuan 030024 Peoples R China

Due to poor metallurgical weldability of magnesium alloy,laser welding crack is still one of the main *** generations of welding crack seriously affected the weld quality and reduce the mechanical properties of welded joints which have become a bottleneck of the magnesium alloy products widely used in the structure *** this paper,az31b magnesium alloy sheet with 2mm thickness was used for this *** forming reason and extending characteristics of the welding cracks were investigated during the Nd:YAG pulsed laser *** results show that welding cracks are mainly solidification crack which were always present in the weld *** welding hot cracks appear multiple furcation phenomenons,and main and branch cracks were intercrystalline *** partial branch crack was mixed intercrystalline and transgranular *** addition,few cracks in the weld were caused due to irregular shape porosity and *** delayed crack weren't observed in the weld after deposited 48 *** the pre-process on the basis,the characteristics and generation mechanism of YAG pulsed laser welding cracks of magnesium alloy were analyzed further.

关键词： az31b magnesium alloy Nd:YAG pulsed laser laser welding welding crack crack extension

az31b/Cu复合材料的扩散焊制备与界面显微组织分析

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稀有金属材料与工程 2014年第2期43卷 475-480页

作者：杜双明刘刚王明静西安科技大学陕西西安710054

采用真空扩散焊工艺,在加热温度500℃、保温时间40 min、压力2.5 MPa、真空度1.0×10-2 Pa下制备了变形镁合金az31b/Cu双金属复合材料,并对复合材料界面区的微观结构和力学性能进行分析,探讨了界面反应层的形成机理。结果表明:铜在镁合... 详细信息

采用真空扩散焊工艺,在加热温度500℃、保温时间40 min、压力2.5 MPa、真空度1.0×10-2 Pa下制备了变形镁合金az31b/Cu双金属复合材料,并对复合材料界面区的微观结构和力学性能进行分析,探讨了界面反应层的形成机理。结果表明:铜在镁合金一侧富集出现晶界渗透现象。镁合金/Cu界面的组织依次为:α-Mg和沿其晶界析出相Mg17(Cu,Al)12/α-Mg/(α-Mg+Mg2Cu)共晶/Cu2Mg金属间化合物/(α-Mg+Mg2Cu)共晶/Cu(Mg)固溶体。硬度在基体两侧到界面中心区域内呈台阶式增加,最高显微硬度达到3510 MPa。Cu2Mg两侧的共晶液相出现具有先后次序,晶界渗透区与Cu2Mg之间先形成Mg-Cu共晶液相,然后共晶液相中的Mg原子穿越Cu2Mg层扩散至Cu侧,在Cu2Mg与Cu(Mg)固溶体之间形成Mg-Cu共晶液相。复合材料的界面抗剪强度达到61 MPa,剪切断裂发生在界面扩散层内,断口由撕裂棱和撕裂棱两边的大小不一的解理台阶构成。

关键词： az31b Cu复合材料扩散焊界面显微组织

az31b镁合金矫直过程中热力耦合模型下中性层偏移规律分析

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稀有金属材料与工程 2021年第12期50卷 4395-4401页

作者：王亚东刘翠荣马立峰李强李玉贵桂海莲太原科技大学材料科学与工程学院山西太原030024 太原科技大学机械工程学院山西太原030024 太原重型机械集团技术中心山西太原030024

为了提高镁合金板材的矫直精度,需要对镁板的中性层偏移规律进行分析。在室温下,镁合金的塑性较差且拉压不对称性也较大。并且镁板在室温下矫直时,压下量的控制不当会导致板材的矫直效果受到严重影响,因此,镁板常采用温矫的方法来提高... 详细信息

为了提高镁合金板材的矫直精度,需要对镁板的中性层偏移规律进行分析。在室温下,镁合金的塑性较差且拉压不对称性也较大。并且镁板在室温下矫直时,压下量的控制不当会导致板材的矫直效果受到严重影响,因此,镁板常采用温矫的方法来提高矫直精度,而且温度是影响镁板拉压不对称性的重要因素。本研究基于Caba2004拉压不对称性屈服准则,利用弹塑性力学的基本理论,推导了az31b镁板在矫直过程中中性层偏移量计算公式,运用AbAQUS有限元软件建立了热力耦合矫直模型,得出了不同温度下的中性层偏移规律,并利用实验对中性层偏移理论进行实验验证。

关键词： az31b 矫直温度拉压不对称性热力耦合中性层偏移