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Effect of cross rolling on the microstructure and mechanical performance of a dual-phase structured Mg-8Li-6Zn-1Y(in wt.%)alloy

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Journal of Materials Science & Technology 2024年第9期176卷 132-144页

作者： Dongliang Wang Daokui Xu Baojie Wang Changjian Yan Shuo Wang Xiangbo Xu Lan Zhang Cuilan Lu Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Binzhou Institute of Technology Binzhou 256606China Shandong Key Laboratory of Advanced Aluminium Materials and Technology Binzhou 256606China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang 110159China Institute of Corrosion Science and Technology Guangzhou 510070China Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

The microstructure and mechanical performance of the unidirectionally and cross-directionally rolled Mg-8Li-6Zn-1Y(in wt.%)sheets have been investigated and *** reveals that after the unidirectional rolling(UR),the broken I-phase particles are aggregated at theα-Mg/β-Li phase ***,the cross-rolling(CR)process can not only severely break the bulk I-phase,but also cause the obviously uniform distribution of I-phase particles in the matrix ***,the average grain size of the CR samples is 3.61μm and about 50%that of the UR *** maximum texture intensities ofα-Mg andβ-Li phases in the CR samples are slightly stronger than those in the UR *** results demonstrate that the CR process can effectively enhance the tensile properties and remarkably reduce the mechanical anisotropy of the *** the UR samples,the yield strength,ultimate tensile strength,and elongation ratio along the rolling direction(RD)are 164 MPa,198 MPa,and 16.4%,whereas those along the transverse direction(TD)are 157 MPa,185 MPa,and 22.0%,*** the CR samples,their mechanical properties are basically the same and the mechanical anisotropy is almost *** yield strength,ultimate tensile strength,and elongation ratio along the cross-rolling direction 1(CRD1)and 2(CRD2)are respectively measured to be 181 MPa and 182 MPa,220 MPa and 218 MPa,20.6%and 20.7%.Failure analysis indicates that for the UR samples being tensile tested along the RD and TD,microcracks are preferentially initiated in the region of aggregated I-phase *** the CR samples being tensile tested along both two cross-rolling directions,the initiation of micro-cracks mainly occurs at the I-phase/matrix phase interfaces and in the interior of matrix phases.

关键词： Magnesium-lithium alloy Cross-rolling I-phase Microstructure mechanical performance

Interface characteristic and mechanical performance of TiAl/Ti_(2)AlNb diffusion bonding joint with pure Ti interlayer

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维普期刊数据库

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Rare Metals 2020年第12期39卷 1402-1412页

作者： Lei Zhu Bin Tang Ming-Xuan Ding Yan Liu Xiao-Fei Chen Shao-Peng Yan Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Shaanxi Key Laboratory of High-performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi'an 710072China

Solid-state diffusion bonding(DB)of TiAl alloy and Ti2 AlNb alloy was carried out using pure Ti as an interlayer at 1000℃under 20 MPa for 60-120 *** effects of bonding times on the interfacial microstructure and mechanical performance of the TiAl/Ti/Ti_(2)AlNb bonded joints at room temperature(RT)were investigated *** results demonstrated that the diffusion layers(DLs)mainly consisted of four characteristic layers,(Ⅰ)single coarseα_(2)phase adjacent TiAl alloy,(Ⅱ)single refinedα_(2)phase at the bonding interface,(Ⅲ)equiaxed/acicularα_(2)phase embedded inβphase adjacent Ti_(2)AtNb alloy and(IV)both equiaxedα_(2)phase and acicular O phase embedded inβphase adj acent Ti_(2)AlNb alloy,*** thickness of the four layers increased with the increasing of the bonding *** growth of DLs is controlled by diffusion and the reaction rate constant k for regionⅠ,Ⅱ,ⅢandⅣare 1.22×10^(-6),1.27×10^(-6),2.6×10^(-7)and 7.7×10^(-7)m·s^(-1/2),***,the interfaceα_(2)grain grows up without *** maximum tensile strength of 281 MPa was maintained at1000℃for 90 min under the pressure of 20 ***,the phase transformation and dynamic recrystallization behavior of the DLs were discussed.

关键词： Sputtering Bonding interface Microstructure Growth kinetics mechanical performance

Preparation and mechanical performance of Rare Earth- Containing Composite Elastomer

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Journal of Rare Earths 2001年第4期19卷 260-265页

作者：邱关明周兰香张明中北里志井上真一冈本弘 Dept. of Mat. and Chem. Eng. Changchun Coll. of Optics. Changchun 130021 China

Rare earth -containing PSBR sheet was prepared by reaction of rare earth alkoxide with quaternary ammonium salt of pyridine modified SBR (PSBR) latex, and then it was blended with natural rubber (NR) to produce rare earth - containing composite elastomer. It is found that mechanical performance can be improved remarkably. Analyzed by infrared spectrometry (IR), differential scanning calorimetry (DSC) and cross-linking densitometry, the relationship between structure and performance was discussed.

关键词： rare earths PSBR latex composite elastomer mechanical performance material structure

Simultaneously enhanced thermal conductivity and mechanical performance of carbon nanotube reinforced ZK61 matrix composite

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Journal of Magnesium and Alloys 2024年第7期12卷 2756-2765页

作者： Fanjing Meng Wenbo Du Xian Du Baohong Zhu Ke Liu Shubo Li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyNo.100 Ping Le YuanChaoyang DistrictBeijing 100124China

Alloying seriously deteriorates the thermal conductivity of magnesium(Mg)alloys,thus,restricts their applications in the fields of computer,communication,and consumer *** order to improve the thermal conductivity of Mg alloys,adding carbon nanotube(CNT)combined with aging treatment is proposed in this work,*** the D-CNT(a kind of dispersed CNT)reinforced ZK61 matrix composite via powder metallurgy,and conducting aging treatment to the *** indicate the as-aged ZK61/0.6 wt.%D-CNT composite achieved an excellent thermal conductivity of 166 W/(mK),exhibiting 52.3%enhancement in comparison with matrix,as well as tensile yield strength of 321 MPa,ultimate tensile strength of 354 of MPa,and elongation of 14%.The simultaneously enhanced thermal conductivity and mechanical performance are mainly attributed to:(1)the embedded interface of the D-CNT with matrix and(2)the coherent interface of precipitates with *** is expected the current work can provide a clue for devising Mg matrix composites with integrated structural and functional performances,and enlarge the current restricted applications of Mg alloys.

关键词： Mg matrix composite Carbon nanotube Interface Thermal conductivity mechanical performance

Enhancement of the mechanical performance of SiCf/Phenolic Composites after High-temperature Pyrolysis Using ZrC/B_(4)C Particles

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1262-1268页

作者： DING Jie LI Yan SHI Minxian HUANG Zhixiong QIN Yan ZHUANG Yingluo WANG Cunku School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The composites were prepared by modifying silicon carbide fiber with particles of zirconium carbide(ZrC)and boron carbide(B_(4)C)and incorporating them into a phenolic resin *** influence of ZrC and B_(4)C on the mechanical performance of SiCf/phenolic composites after high-temperature pyrolysis was studied through flexural performance *** results show that the composite material has good thermal stability and high-temperature mechanical *** static ablation at 1400℃ for 15 minutes,the flexural strength of the composite material reaches 286 MPa,which is still 7.3%higher than at room temperature,indicating that the composite material still has good mechanical properties even after heat treatment at 1400℃.

关键词： SiC fiber phenolic resin mechanical performance high-temperature pyrolysis

Effect of Cerium on mechanical performance and Electrical Conductivity of Aluminum Rod for Electrical Purpose

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Journal of Rare Earths 2006年第Z2期24卷 355-357页

作者：李鹏飞邬志刚王云利高喜柱王再运李志强 College of Materials Science and Engineering Inner Mongolia University of Technology Baotou Aluminum Co. Ltd.

The effect of rare earth element Ce on mechanical performance and electrical conductivity of aluminum rod for electrical purpose were studied under industrial production condition. Using optical microscope, SEM, TEM, EDS and X-ray diffractometer, the microstructure and phase composition of aluminum rod were measured and analyzed. The results indicate that the content of rare earth element Ce is between 0.05% -0.16% in the aluminum rod for electrical purpose. Its tensile strength is enhanced to some extent. The research also discovers that the tensile strength is enhanced remarkably with impurity element Si content increases. Because influence of Si is big to the conductivity, the Si content should be controlled continuously strictly in the aluminum for electrical purpose. Adding rare earth element Ce reduces the solid solubility of Si in the aluminum matrix, and the negative effect of Si on the aluminum conductor reduces effectively. So the limit of in Si content in aluminum rod for electrical purpose can be relaxed moderately.

关键词： rare earth element aluminum rod for electrical purpose mechanical performance electrical conductivity

Dry-regulated hydrogels with anisotropic mechanical performance and ionic conductivity

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Chinese Chemical Letters 2022年第2期33卷 871-876页

作者： Ping Li Yi Liu Ziang Wang Xuemei Xiao Guozhe Meng Xiaolin Wang Hong-Lei Guo Hui Guo School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Pharmacy and State Key Laboratory of Quality Research in Chinese Medicine Macao University of Science and TechnologyMacaoChina

Nature consists of various soft tissues with well-ordered hierarchical anisotropic structures, which play essential roles in biological systems to exhibit particular functions. Mimicking bio-tissues, synthetic hydrogels with anisotropic structures have received considerable attention in recent years. However, existing approaches to fabricate anisotropic hydrogels often require complicated procedures, which are timeconsuming and labor-demanding. Inspired by the dry-induced crystallization phenomenon, we report a simple yet effective prestretching-drying-swelling method to afford anisotropic crystalline polyvinyl alcohol hydrogels. Owing to the distinct anisotropic microstructure, the hydrogels demonstrate excellent mechanical properties with noticeable directional distinction. It is revealed that both the enhancing of pre-orientation strain and the extending of heating time make the hydrogels with better mechanical properties and more remarkable anisotropicity. Owing to the anisotropically aligned structure, the hydrogels exhibit remarkably differential ionic conductivity: the difference between the parallel and vertical conductivity of the same sample can reach as high as 6.6 times, making the materials possible candidates as nano-conductive materials. We anticipate that this simple yet effective approach may become highly useful for fabricating oriented hydrogels and endow the materials with more promising application prospects in the future.

关键词： Crystalline hydrogels Anisotropicity Dry process mechanical performance Differential conductivity

Effect of High-temperature Annealing on mechanical performance and Microstructures of Different Oxygen SiC Fibers

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Journal of Wuhan University of Technology(Materials Science) 2018年第4期33卷 778-782页

作者：刘卫丹 ZHAO Yan DONG Anqi School of Materials Science and Engineering Beihang UniversityBeijing 100086China

In order to explore the effect of high-temperature annealing on the mechanical performances and microstructures of different oxygen SiC fibers, two types of silicon carbide（SiC）-based fibers, specified as XD-SiC fibers（low oxygen） and Nicalon-201 fibers（high oxygen）, were annealed in Ar for 1 h at 800 ℃, 1 000 and 1 200 ℃, respectively. mechanical properties of these fibers were characterized via a monofilament tensile method, with observation of the damaged monofilament by SEM. Also, the effects of annealing on the microstructure and chemical compositions of the fibers were studied. The experimental results indicated that the tensile strength decreased with the increase of annealing temperatures,after annealing-treatment at 1200℃, XD-SiC fibers remained 84% of its original strength, while Nicalon-201 fibers remained only 58% of its original strength. Crystallization and chemical composition of the fibers are the dominating factors for their mechanical performance at high temperatures. The microstructure changes of XD-SiC fibers are mainly composed of the growth of β-SiC, for Nicalon-201 fibers, evaporation of gases is the main change for microstructure.

关键词： SiC fibers annealing-treatment mechanical performance microstructures

Structure and mechanical performance of Nitrogen Doped Diamond-like Carbon Films

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Journal of Materials Science & Technology 2007年第4期23卷 491-494页

作者： Huayu ZHANG Liang-xue LIU Yulei WANG Hongtao MA Fanxin LIU Harbin Institute of Technology Shenzhen Graduate School Shenzhen518055 China SAE Technologies Development （Dongguan） Co. Ltd. Dongguan 523087 China

Nitrogen doped diamond-like carbon （DLC：N） films were prepared by electron cyclotron resonance chemical vapor deposition （ECR-CVD） on polycrystalline Si chips. Film thickness is about 50 nm. Auger electron spectroscopy （AES） was used to evaluate nitrogen content, and increasing N2 flow improved N content from 0 to 7.6%. Raman and X-ray photoelectron spectroscopy （XPS） analysis results reveal CN-sp^3C and N-sp^2C structure. With increasing the N2 flow, sp^3C decreases from 73.74% down to 42.66%, and so does N-sp^3C from 68.04% down to 20.23%. The hardness decreases from 29.18 GPa down to 19.74 GPa, and the Young＇s modulus from 193.03 GPa down to 144.52 GPa.

关键词： Nitrogen doped diamond-like carbon films ECR-CVD Structure mechanical performance