检索结果-南通市图书馆

Synthesis of C_f/TiAl_3 Composite by Infiltration-In Situ Reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2009年第6期25卷 803-806页

作者： Yanmei Liu ziyang xiu Yongliang Guo Longtao Jiang Wensu Yang Gaohui Wu School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Research Academy of Science and Industry Technology Harbin Institute of Technology Harbin 150001 China Analysis and Measurement Center Harbin Institute of Technology Harbin 150001 China

Infiltration-in situ reaction synthesis of Cf/TiAl3 composite was investigated. The as-cast material was obtained by titanium particles, carbon fibers and pure aluminum. Titanium particles and carbon fibers were mixed and pressed to form a preform firstly, and then molten pure aluminum was pressed into the preform, subsequently, cooled rapidly. In situ reaction samples were obtained by heating the as-cast material from 600 to 1000℃ for I h. The microstructural evolution of in situ reaction samples was analyzed by scanning electron microscopy and energy dispersive X-ray. In addition, the phase composition of products was inspected by X-ray diffraction. Experimental results showed that the dominant product of TiAl3 and a small amount of Al4C3 were formed at low temperature. While TiAl3 was not stable at high temperature, along with its decrease, TiC phase became favorable. In the final products, TiAl3, TiC and Al4C3 were detected. Thus, the in situ reaction for Ti-Al-C system composite proceeded a formed-decomposed-precipitated mechanism.

关键词： Composites Ti-Al Intermetallics In situ reaction Microstructure

Microstructure and Mechanical Properties of 45 vol.%SiC_p/7075Al Composite

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2015年第9期31卷 930-934页

作者： ziyang xiu Wenshu Yang Ronghua Dong Murid Hussain Longtao Jiang YongXing Liu Gaohui Wu State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Department of Material Science and Engineering Harbin Institute of Technology Department of Chemical Engineering COMSATS Institute of Information Technology

Microstructure and mechanical behavior of high volume content SiCp/7xxxAl composites have not been explored yet. Therefore, in the present work, 45 vol.% SiCp/7075Al composite has been prepared by pres- sure infiltration method. High density dislocations were found around SiC/Al interface in SiCp/7075Al composite after water-quenching and aging treatment. Fine dispersed nano-η＇ phases were observed after the aging treatment. Adverse to other SiCp/Al composites prepared by the pressure infiltration method, an interface layer was observed between SiC particles and AI matrix. Furthermore, high-resolution trans- mission electron microscopy （HRTEM） observation indicated that this interface layer was coherent/semi- coherent with that of the SiC particles. 45 vol.% SiCp/7075Al composite demonstrated high tensile strength （630 MPa） and micro-ductility. Compared to aged SiCp/2024Al composite, the aged SiCp/7075Al com- posite showed an increase of about 200% in the tensile strain and 90% in the tensile strength, respectively. It is speculated that nano-η＇ phases in the Al matrix significantly contributed to the strengthening effect while the interface layer between SiC and AI matrix might be beneficial to the strength and plasticity of SiCp/7075Al composite.

关键词： Metal matrix composite7075Al InterfaceNano precipitationMechanical properties

Quantitative study of dimensional stability mechanism and microstructure evolution during precipitation process of 2024Al alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第31期90卷 85-94页

作者： Youfang Cao Longtao Jiang Deng Gong Guoqin Chen ziyang xiu Yangming Cheng xiufang Wang Gaohui Wua School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China

In this paper,we were devoted to quantitatively analyzing the dimensional change of 2024 Al alloy during the aging process.Types of precipitates have been defined and the corresponding volume fraction has been measured with Transmission Electron Microscopy(TEM)and Three-Dimensional Atom Probe Tomography(3 D-APT).Guinier-Preston-Bagaryatsky(GPB)zone(0.86 vol.%)was found after aging for 8 h.GPB zone(0.17 vol.%)and S'phase(1.02 vol.%)was found after aging for 24 h.The reduced dimensional change was attributed to the reduction of matrix lattice parameter.Relative to the initial supersaturated solid solution state,the lattice strain of-2.79×10^(-5)and-5.16×10^(-5)was produced after 8 h and 24 h aging respectively.The difference of the lattice parameters between the precipitates and matrix was also considered.A model was established to quantitatively describe the relationship between the precipitation process and dimensional change of 2024 Al alloy.

关键词： Aluminum alloy Aging Atom probe tomography(APT) Dimensional stability Precipitate

Microstructure and Properties of M40 Carbon Fibre Reinforced Mg-Re-Zr Alloy Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2009年第3期25卷 423-426页

作者： Gaohui Wu Meihui Song ziyang xiu Ning Wang Wenshu Yang School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

M40 carbon fibre reinforced rare earth magnesium alloy ZM6 composites with fibre volume fraction about 60% were fabricated by pressure infiltration method. The microstructure, interracial morphology, and precipitation were studied by scanning electron microscopy, transmission electron microscopy, and energy dispersive X- ray spectrometer. It was shown that the interfaces between Mg alloy and fibres were well bonded and free from cracks. The Mg12Nd phase was preferentially precipitated at the fibre/matrix interfaces, leading to the segregation of Nd at the interfaces and the dramatic decrease of Mg12Nd precipitation in the matrix far from interfaces. Crystal defects such as high-density dislocations and twins were observed in the matrix near the fibre/matrix interface. A high bending strength （1393 MPa） and elastic modulus （190 GPa） were achieved in M40/ZM6 composite.

关键词： Magnesium matrix composites Microstructure Dislocations Twin

Mechanical Properties of C_f/Mg Composites Fabricated by Pressure Infiltration Method

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2010年第10期26卷 931-935页

作者： Meihui Songt Gaohui Wu Wenshu Yang Wei Jia ziyang xiu Guoqin Chen School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The carbon fibers and the woven reinforced magnesium matrix composites were fabricated by pressure infiltration method. Effects of fiber species, fiber arrangement, hybrid particles and environment temperature on microstructures and properties of the composite were studied. Results showed that the mechanical properties at ambient temperature were affected by interfacial reaction. The magnesium matrix composites reinforced with graphite fibers showed higher strength and elastic modulus due to less interfacial reaction. During loading, the fibers were pulled out and the load was transferred through the interfaces, then the fiber bundles were fractured, finally the whole specimen failed. The introduction of hybrid SiC particles during fabrication can improve the mechanical properties of the magnesium matrix composites. Moreover, taking orthogonal carbon fiber woven as reinforcement can modify the anisotropy and reliability of materials.

关键词： Magnesium matrix composites Mechanical property Interfacial reaction Pressure infiltration

Reaction procedure of a graphite fiber reinforced Ti-Al composite produced by squeeze casting-in situ reaction

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2010年第1期29卷 98-101页

作者： WU Gaohui LIU Yanmei xiu ziyang JIANG Longtao YANG Wenshu School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Research Academy of Science and Industry Technology Harbin Institute of Technology Harbin 150001 China

The in situ reaction procedure and microstructure evolution of a graphite fiber reinforced Ti-Al composite （Grf/Ti-Al） was investigated, and the stability of TiAl3 at high temperature was discussed. As-cast material was prepared by pressing molten pure aluminum into a preform, which was composed of titanium particles and graphite fibers. The in situ reaction procedure of the as-cast material was investigated by differential scanning calorimetry （DSC）, and phases in the products were detected by X-ray diffraction （XRD）. Experimental results showed that TiAl3 was formed first. With an increase in temperature, TiC and Al4C3 were observed, but TiAl3 decreased. In the final product, Al2O3 and TiO2 were observed. It was considered that the previous forming TiAl3 decomposed, then TiC precipitated, and subsequently, oxidation resulted in the formation of Al2O3 and TiO2.

关键词： intermetallics titanium aluminide composites microstmcture squeeze casting in situ reaction

Microstructure and Mechanical Properties of AlSiTiCrNiCu Particles Reinforced Al6061 Composites by SPS and HPS Process

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2022年第1期37卷 1-12页

作者：王智君 ZHOU Shengjie SHAO Puzhen SUN Kai 张强修子扬肖海英 WU Gaohui School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing Technology School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China Chengdu Holy Industry&Commerce Corp.Ltd.(Group) Chengdu 611936China

Three groups of AlSiTiCrNiCu high entropy alloy(HEA)particles reinforced Al606l composites were fabricated by spark plasma sintering at 520 and 570℃(S520,S570)and by hot-pressed sintering at 570℃(H570).The AlSiTiCrNiCu(AST)particles used as reinforcements were synthesized by mechanical alloying.The influences of the sintering process on the microstructure and mechanical properties of composites were investigated.The results showed that the AST particles had a near-equiatomic composition with a single BCC structure.The sintering temperature and time had a coupling influence on the interfacial microstructure.S520 had hardly reaction products and slight interfacial diffusion,and the AST particles were completely high entropy.Intense interfacial reactions happened on S570 and H570 with the same reaction products.The element diffusion of S570 was focused on the edge of the AST particles with partial loss of high entropy.Complete element diffusion and entire loss of high entropy of AST particles happened on H570.The differences in the microstructure caused by the three preparation methods led to the changes in mechanical properties and fracture mechanisms of composites.

关键词： high entropy alloys mechanical alloying Al matrix composites spark plasma sintering hot-pressed sintering

钨丝增强铜基复合材料的动态力学性能及断裂特性

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2011年第9期40卷 1580-1583页

作者：吴哲武高辉康鹏超修子扬哈尔滨工业大学黑龙江哈尔滨150001

通过渗流铸造的方法制备出Wf/Cu82Al10Fe4Ni4复合材料,采用分离式霍普金森压杆(SHPB)和扫描电镜(SEM)研究其动态压缩行为及断裂特性。结果表明:复合材料界面结合紧密,受冲击时体现出良好的界面结合强度;在应变率为2000s-1下动态压缩材... 详细信息

通过渗流铸造的方法制备出Wf/Cu82Al10Fe4Ni4复合材料,采用分离式霍普金森压杆(SHPB)和扫描电镜(SEM)研究其动态压缩行为及断裂特性。结果表明:复合材料界面结合紧密,受冲击时体现出良好的界面结合强度;在应变率为2000s-1下动态压缩材料发生部分塑性变形,局部表面出现裂纹;在应变率为3000s-1下动态压缩材料的动态压缩强度达到2500MPa,材料内部出现钨丝劈裂、钨丝弯曲断裂以及基体合金断裂3种破坏模式。同时,在材料的断裂面上出现大量熔化带,分析认为熔化是随着应变率的提高而出现的,它改变了复合材料的断裂方式,加速了Wf/Cu82Al10Fe4Ni4复合材料的整体失效。

关键词：钨丝复合材料霍普金森压杆(SHPB) 动态压缩断裂特性

三维封装电迁移Cu互连线的多物理场模拟仿真

在线全文

学校读者我要写书评

暂无评论

材料导报 2021年第2期35卷 2133-2138页

作者：张墅野鲍天宇修子扬何鹏哈尔滨工业大学先进焊接与连接国家重点实验室

随着三维封装微互连尺寸向亚微米发展,电流密度大、应力大、散热困难等问题愈发严重,原子尺度迁移失效现象逐渐成为超大规模集成电路不可忽视的可靠性问题。铜比铝的电阻率低,抗电迁移性能更好,是新一代的可靠互连材料,但是对铜互连的... 详细信息

随着三维封装微互连尺寸向亚微米发展,电流密度大、应力大、散热困难等问题愈发严重,原子尺度迁移失效现象逐渐成为超大规模集成电路不可忽视的可靠性问题。铜比铝的电阻率低,抗电迁移性能更好,是新一代的可靠互连材料,但是对铜互连的原子迁移研究仍有不足。现有的电迁移(Electromigration)可靠性解析化模型主要针对单根金属线恒定温度情形下的电迁移分析,这种方法虽然计算较为简单,但是对现实情况的指导意义较小,主要原因:一是现实情况下高密度集成电路中存在温度梯度,二是互连线的三维结构对互连线的温度以及电流分布有重要影响,而这些参数严重影响着金属原子的抗电迁移性能。本工作提出一种新的电迁移仿真建模方法,通过COMSOL多物理场软件建立了经典三维Cu互连线结构。通过有限元仿真得到三维互连线的温度、电流密度和应力分布,获得了更优的数据仿真结果。结果显示,金属互连线中电流在直角内侧有严重的淤积现象,电迁移在互连线转折处最为剧烈;高温区域位于直角内外侧之间,热迁移的程度随着温度的升高而升高;高应力区域主要是互连线的外边缘处,但是应力迁移在总体电迁移中占比较小,几乎可以忽略。另外,Cu互连线的抗电迁移性能总体优于Ag互连线,是优异的高密度集成电路导体材料。

关键词：电迁移互连线原子扩散通量散度温度影响材料影响